* PR Checks: use `macos-12` runners for CLI v. < 2.15.1
Prior to CLI v2.15.1, MacOS ARM runners were not supported by the build tracer. "macos-latest" is now an ARM runner, so we run these tests on the old CLIs on Intel runners instead.
* Log a warning if SIP is disabled and CLI is < 2.15.1
* Add changenote for SIP-disabled support on old CLI versions
* Set up Python 3.11 for all MacOS checks
Refactor the existing classes of configuration errors into their own file; consolidate the place we check for configuration errors into `codeql.ts`, where the actual command invocations happen.
Also, rename the `UserError` type to `ConfigurationError` to standardize on a single term.
We want to respect cgroup constraints so that when we run in a container, we respect the limits set for the container rather than use the host OS's number of cores.
We check both `/sys/fs/cgroup/cpuset.cpus.effective` (`cgroup v2`) and `/sys/fs/cgroup/cpuset.cpus` (`cgroup v1`) to find the number of cores available. We also check `sys/fs/cgroup/cpu.max` (v1, v2) to calculate the number of cores from the limits set in this file.
The max threads value is set to the minimum of these values, and if no values were found in these files, we default to the original value of the host OS.
The amount of RAM given to the CodeQL evaluator is the machine's total
memory size, minus a reserved amount. Currently, the reserved amount is
fixed at 1 GB (or 1.5 GB on Windows). When the scaling_reserved_ram
feature flag is enabled, we also add 2% of the total memory size to the
reserved amount. This allows for the fact that the kernel will consume
more RAM (e.g. for page tables) on machines with more physical RAM.
