ci: add macOS support to test matrix and configure build cache

- Add macos-latest to the test matrix alongside ubuntu-latest
- Set go-build cache path for macOS separately

Signed-off-by: appleboy <[email protected]>

Author: appleboy

.github/workflows/testing.yml

@@ -40,11 +40,13 @@ jobs:
   test:
     strategy:
       matrix:
-        os: [ubuntu-latest]
+        os: [ubuntu-latest, macos-latest]
         go: [1.24]
         include:
           - os: ubuntu-latest
             go-build: ~/.cache/go-build
+          - os: macos-latest
+            go-build: ~/Library/Caches/go-build
     name: ${{ matrix.os }} @ Go ${{ matrix.go }}
     runs-on: ${{ matrix.os }}
     env: