[clang] [analyzer] Explicitly register NoStoreFuncVisitor from alpha.unix.cst… (PR #108373)

[Donát Nagy via cfe-commits]

https://github.com/NagyDonat approved this pull request.

The change looks good to me and as it is fairly innocent, I think we can merge it soon (assuming that we don't get additional remarks from somebody else).

When you're merging this change please write a commit message that is self-contained and doesn't reference our codechecker server (because those links will eventually succumb to link rot, while the git commit log is eternal). I know that the graphical representation of the execution path is more readable than plain-text alternatives but you could explain the goals of the change e.g. by referencing the test file that you added. 

https://github.com/llvm/llvm-project/pull/108373