Revert "Example nix-based CI workflow (#1195)" (#1255)

This reverts commit 7676cbf.

Similar to #1250 but just
mechanically reverting the commit in question.

.github/workflows/ci.yml

@@ -2,7 +2,7 @@ name: CI
 
 on:
   push:
-    branches: ["main"]
+    branches: [ "main" ]
   pull_request:
     types:
       - opened
@@ -28,29 +28,16 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
+      - name: Install rust toolkit
+        uses: ./.github/actions/rust
         with:
           local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Compile and archive all the tests
-        run: nice cargo nextest archive --locked --features="enable_poseidon_starks" --all-targets --archive-file mozak-vm-tests.tar.zst
+      - name: Compile
+        run: nice cargo nextest run --no-run --locked --features="enable_poseidon_starks" --all-targets
 
-      - name: Run all the tests from the archive
-        run: MOZAK_STARK_DEBUG=true nice cargo nextest run --no-fail-fast --archive-file mozak-vm-tests.tar.zst
-
-  run-examples:
-    needs: check-runner
-    runs-on: ${{ needs.check-runner.outputs.runner-label }}
-    steps:
-      - uses: actions/checkout@v4
-
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
-        with:
-          local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Test
+        run: MOZAK_STARK_DEBUG=true nice cargo nextest run --no-fail-fast --locked --features="enable_poseidon_starks" --all-targets
 
       - name: Build and run examples
         run: |
@@ -63,8 +50,8 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
+      - name: Install rust toolkit
+        uses: ./.github/actions/rust
         with:
           local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}
 
@@ -81,26 +68,28 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
+      - name: Install rust toolkit
+        uses: ./.github/actions/rust
         with:
           local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}
 
       - name: Build all examples
         run: |
-          cd examples-builder && cargo build --all-features
+          cd examples-builder
+          cargo build --all-features
 
   cargo-fmt:
     needs: check-runner
     runs-on: ${{ needs.check-runner.outputs.runner-label }}
     steps:
       - uses: actions/checkout@v4
 
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
+      - name: Install rust toolkit
+        uses: ./.github/actions/rust
         with:
           local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}
 
+
       - name: Run fmt
         run: cargo fmt --all --check
 
@@ -121,8 +110,8 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Install CI deps
-        uses: ./.github/actions/ci-deps
+      - name: Install rust toolkit
+        uses: ./.github/actions/rust
         with:
           local-cache: ${{ needs.check-runner.outputs.runner-label == 'self-hosted' }}