Replace nvm/asdf with native CircleCI node installation (readthedocs#…

…10174)

I'm not really sure how/why this was working. It seems this was using
some mix of asdf and nvm (??).

I removed some hacks and replaced it with the node orb that we're using
to install Node in other repositories.

.circleci/config.yml

@@ -2,6 +2,7 @@ version: 2.1
 
 orbs:
   codecov: codecov/codecov@3.2.2
+  node: circleci/node@5.1.0
 
 jobs:
   tests:
@@ -37,21 +38,16 @@ jobs:
   checks:
     docker:
       - image: 'cimg/python:3.10'
-        environment:
-          NODE_VERSION: 10.17.0
     steps:
       - checkout
       - run: git submodule sync
       - run: git submodule update --init
       - run: pip install --user 'tox<5'
       - run: tox -e pre-commit
       - run: tox -e migrations
-      - run: scripts/circle/install_node.sh
-      - run:
-          name: Add node to the path
-          command: |
-            echo 'export PATH=~/.nvm/versions/node/v${NODE_VERSION}/bin:$PATH' >> $BASH_ENV
-            source $BASH_ENV
+      - node/install:
+          node-version: '10.17.0'
+      - run: npm ci
       - run: tox -e eslint
 
 workflows: