macos: use Xcode 14.2
We currently use xcode13.3 for this build, however, It currently makes our preparatory steps in CI build for osx to hung as shown at !3116 (closed) .
- We have not noticed this blockage when using xcode 14.2. Here we update the osx build to use xcode 14.2.
- We also address some build warnings in this MR.
Edited by Vicente Bolea