Fixup capitalization, back out concurrency changes

Author: LilithHafner

.github/workflows/CI.yml

@@ -6,13 +6,6 @@ on:
       - main
     tags: '*'
 
-concurrency:
-  # group by workflow and ref; the last slightly strange component ensures that for pull
-  # requests, we limit to 1 concurrent job, but for the default repository branch we don't
-  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.ref_name != github.event.repository.default_branch || github.run_number }}
-  # Cancel intermediate builds, but only if it is a pull request build.
-  cancel-in-progress: ${{ startsWith(github.ref, 'refs/pull/') }}
-
 # needed to allow julia-actions/cache to delete old caches that it has created
 permissions:
   actions: write
@@ -37,13 +30,13 @@ jobs:
           - ''  # default arch, usually x64 but for macOS also aarch64
           - x86
         exclude:
-          - os: macos-latest # Apple Silicon
+          - os: macOS-latest # Apple Silicon
             arch: x86
-          - os: macos-latest # Apple Silicon
+          - os: macOS-latest # Apple Silicon
             version: '1.0'
             arch: ''
         include:
-          - os: macos-latest # Apple Silicon
+          - os: macOS-latest # Apple Silicon
             version: '1.0'
             arch: 'x64'  # run x86_64 build of Julia under Rosetta 2 emulation
     steps: