feat(release): automate release via release-please (testcontainers#429)

# changes

- add `release-please` as the release automation tool
- refactor "install python" into a reusable local action
- build and test with Python `3.12` - seems it didn't take much extra
effort

# notes

-  previously, the actual "releases" here on GitHub was a mess 
  - `3.7.1` is the latest on PyPI 
  - only exists as a tag on this repo, no release notes
- the latest "release" is put out later than some of the higher version
tags
- `.github/.release-please-manifest.json` -> went with the sha from
`3.7.1` which then `release-please` will take as "latest live version",
also made `3.7.1` in the manifest

---------

Co-authored-by: Balint Bartha <totallyzen@users.noreply.github.com>

Author: totallyzen

.github/.release-please-manifest.json

@@ -0,0 +1,3 @@
+{
+    ".": "3.7.1"
+}

.github/actions/setup-env/action.yml

@@ -0,0 +1,20 @@
+name: setup-env
+description: set up the python environment
+
+inputs:
+  python-version:
+    description: "The python version to install and use"
+    default: "3.12"  # we default to latest supported
+    required: false
+
+runs:
+  using: composite
+  steps:
+    - name: Setup Poetry
+      run: pipx install poetry
+      shell: bash
+    - name: Setup python ${{ inputs.python-version }}
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ inputs.python-version }}
+        cache: poetry

.github/release-please-config.json

@@ -0,0 +1,10 @@
+{
+    "release-type": "python",
+    "bootstrap-sha": "28e3a471c32c1036dd5e37df13cdde3b1ba91000",
+    "packages": {
+        ".": {
+            "package-name": "testcontainers"
+        }
+    },
+    "$schema": "https://raw.githubusercontent.com/googleapis/release-please/main/schemas/config.json"
+}

.github/workflows/attention-label.yml.disabled

@@ -61,13 +61,10 @@ jobs:
           gh run watch ${{ github.run_id }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      - name: Setup Poetry
-        run: pipx install poetry
-      - name: Setup python ${{ matrix.python-version }}
-        uses: actions/setup-python@v4
+      - name: Set up Python
+        uses: ./.github/actions/setup-env
         with:
           python-version: ${{ matrix.python-version }}
-          cache: poetry
       - name: Install Python dependencies
         run: poetry install -E ${{ matrix.module }}
       - name: Run tests

.github/workflows/ci-community.yml

@@ -11,19 +11,17 @@ on:
 jobs:
   test:
     strategy:
+      fail-fast: false
       matrix:
         os: [ ubuntu ]
-        python-version: ["3.9", "3.10", "3.11"]
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
     runs-on: ${{ matrix.os }}-latest
     steps:
       - uses: actions/checkout@v4
-      - name: Setup Poetry
-        run: pipx install poetry
-      - name: Setup python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
+      - name: Set up Python
+        uses: ./.github/actions/setup-env
         with:
           python-version: ${{ matrix.python-version }}
-          cache: poetry
       - name: Install Python dependencies
         run: poetry install --all-extras
       - name: Run twine check

.github/workflows/ci-core.yml

@@ -9,17 +9,14 @@ on:
     branches: [main]
 
 jobs:
-  all:
+  python:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - name: Setup Poetry
-        run: pipx install poetry
-      - name: Setup python 3.9
-        uses: actions/setup-python@v5
+      - name: Setup Env
+        uses: ./.github/actions/setup-env
         with:
-          python-version: 3.9
-          cache: poetry
+          python-version: "3.9"  # the pre-commit is hooked in as 3.9
       - name: Install Python dependencies
         run: poetry install
       - name: Install pre-commit

.github/workflows/ci-lint.yml

@@ -10,14 +10,11 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - name: Setup Poetry
-        run: pipx install poetry
-      - name: Setup python
-        uses: actions/setup-python@v5
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: ./.github/actions/setup-env
         with:
           python-version: "3.11"
-          cache: poetry
       - name: Install Python dependencies
         run: poetry install --all-extras
       - name: Build documentation

.github/workflows/docs.yml

@@ -0,0 +1,19 @@
+name: lint-pr
+
+on:
+  pull_request:
+    types:
+      - opened
+      - edited
+      - synchronize
+
+permissions:
+  pull-requests: read
+
+jobs:
+  validate:
+    name: validate-pull-request-title
+    runs-on: ubuntu-latest
+    steps:
+      - name: validate pull request title
+        uses: kontrolplane/pull-request-title-validator@ab2b54babb5337246f4b55cf8e0a1ecb0575e46d  #v1

.github/workflows/pr-lint.yml

@@ -0,0 +1,35 @@
+name: Release Please
+
+on:
+  push:
+    branches: [ main ]
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    outputs:
+      release_created: ${{ steps.track-release.outputs.release_created }}
+    steps:
+      - uses: google-github-actions/release-please-action@v4
+        id: track-release
+        with:
+          manifest-file: .github/.release-please-manifest.json
+          config-file: .github/release-please-config.json
+  publish:
+    runs-on: ubuntu-latest
+    environment: release
+    permissions:
+      id-token: write
+    needs:
+      - release
+    if: ${{ needs.release.outputs.release_created }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: ./.github/actions/setup-env
+      - name: build package
+        run: poetry build
+      # this action uploads packages from the `dist/` directory, which poetry has built in the previous step
+      # usable once we set up trusted publishing, see https://docs.pypi.org/trusted-publishers/using-a-publisher/
+      - name: push package
+        uses: pypa/gh-action-pypi-publish@release/v1