Try selecting Xcode 15.3

Reference:
actions/runner-images#8282 (comment)

Signed-off-by: Julien Jerphanion <git@jjerphan.xyz>

.github/workflows/osx.yml

@@ -28,6 +28,14 @@ jobs:
  - name: Checkout code
  uses: actions/checkout@v3
 
+ # For a complete overview of all available pieces of software, see:
+ # https://github.com/actions/runner-images/blob/macos-14-arm64/20240402.2/images/macos/macos-14-arm64-Readme.md
+ - name: List all the Xcode installations
+ run: sudo ls -1 /Applications | grep "Xcode"
+
+ - name: Select Xcode 15.3
+ run: sudo xcode-select -s /Applications/Xcode_15.3.app/Contents/Developer
+
  - name: Set conda environment
  uses: mamba-org/setup-micromamba@main
  with: