Try to fix macOS CI steps (#128)

Explicitly skip old, broken macOS CI steps, expand LTS's in CI.

Author: jkeuhlen

.github/workflows/tests.yml

@@ -14,7 +14,20 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        resolver: [nightly, lts-19, lts-18, lts-17, lts-16, lts-14]
+        resolver: [nightly, lts-24, lts-23, lts-22, lts-21, lts-20, lts-19, lts-18, lts-17, lts-16, lts-14]
+        exclude:
+          # Exclude older LTS versions for macOS ARM64 due to LLVM compatibility issues
+          # LTS 20+ use newer GHC versions that work better with current LLVM
+          - os: macos-latest
+            resolver: lts-19
+          - os: macos-latest
+            resolver: lts-18
+          - os: macos-latest
+            resolver: lts-17
+          - os: macos-latest
+            resolver: lts-16
+          - os: macos-latest
+            resolver: lts-14
 
     steps:
       - name: Clone project
@@ -29,6 +42,12 @@ jobs:
 #          restore-keys: |
 #            ${{ runner.os }}-${{ matrix.resolver }}-
 
+      - name: Setup Stack
+        uses: haskell-actions/setup@v2
+        with:
+          enable-stack: true
+          stack-no-global: true
+
       - name: Build and run tests
         shell: bash
         run: |