Re: [PATCH 5/5] ci: update macOS versions under test

Cirrus CI has stoppped offering multiple versions of macOS images. There is now only 1 single image, but with multiple XCode versions pre-installed, selectable using the 'xcodes' app: $ xcodes list | grep Installed 15.2 (15C500b) (Installed) 15.3 (15E204a) (Installed) 15.4 (15F31d) (Installed, Selected) 16.0 (16A242d) (Installed) $ clang -v Apple clang version 15.0.0 (clang-1500.3.9.4) Target: arm64-apple-darwin23.6.0 Thread model: posix InstalledDir: /Applications/Xcode_15.4.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin $ xcodes select 16.0 xcodes requires superuser privileges to select an Xcode macOS User Password: Selected /Applications/Xcode_16.app/Contents/Developer $ clang -v Apple clang version 16.0.0 (clang-1600.0.26.3) Target: arm64-apple-darwin23.6.0 Thread model: posix InstalledDir: /Applications/Xcode_16.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin Any Cirrus CI jobs using an unsupported macOS image name will get forcably changed at runtime to bot the only permitted image, currently sonoma. IOW, our attempts to test multiple versions were not doing anything useful, as evidenced by this message shown in the Cirrus CI web pages for job tasks: "Only ghcr.io/cirruslabs/macos-runner:sonoma is allowed. Automatically upgraded." Replace (failed) testing of multiple macOS versions, with testing of multiple XCode versions - 15.4 and 16.0