[llvm] [workflows] Add post-commit job that periodically runs the clang static analyzer (PR #94106)

[Artem Dergachev via llvm-commits]

haoNoQ wrote:

Hmm, in this case could this also be the source of performance problems? Like it's swapping or something? Should we try to decrease our `-j`?

If it's just one specific file that goes OOM every single time, then we can exclude that file from analysis by wrapping it in:
```
#ifndef __clang_analyzer__
// the file
#endif
```
But in this case I should take a look at this file. It could be that there's some really weird code that dodges all our limits. (Historically it's been very long initializer lists that we try to represent perfectly in symbolic memory and they count as 1 node for the purposes of `max-nodes`.)

And yeah we should `|| true` the analyzer command either way. No reason to block on this.

https://github.com/llvm/llvm-project/pull/94106