Some projects observed intermittent build timeouts with Swift.
In case this happens, and our CodeQL-level mitigations do not prevent the problem, we want to avoid using up 6h of the customer's billed macOS Actions minutes (which is the default timeout), so we suggest a reduced timeout of 2h.
This value is chosen to accommodate the total job time (build + CodeQL extraction + CodeQL analysis) we expect for large Swift projects. We may choose to adjust it in future.
CodeQL Swift analysis is best supported on macOS.
In preparation for CodeQL supporting Swift analysis in beta,
adjust the CodeQL starter workflow template to run the `swift` matrix job on `macos-latest`, and all other matrix jobs on
`ubuntu-latest`. This does not affect the matrix itself.
Aditya Sharad