ci: don't lint and test for Emacs 27.2

Linting isn't useful right now when we have a mixture of names.

Add 27.2 to the matrix because it's useful to test a stable version.

.github/workflows/test.yml

@@ -38,6 +38,7 @@ jobs:
       matrix:
         emacs_version:
           - snapshot
+          - 27.2
     steps:
     - uses: purcell/setup-emacs@master
       with:
@@ -54,12 +55,6 @@ jobs:
       run: |
         ./makem.sh -vv --sandbox $SANDBOX_DIR --install-deps --install-linters
 
-    # The "all" rule is not used, because it treats compilation warnings
-    # as failures, so linting and testing are run as separate steps.
-    - name: Lint
-      continue-on-error: false
-      run: ./makem.sh -vv --sandbox $SANDBOX_DIR lint
-
     - name: Test
       if: always()  # Run test even if linting fails.
       run: ./makem.sh -vv --sandbox $SANDBOX_DIR test