[clang] [mutation analyzer] enhance stability for `hasAnyInit` matcher (PR #122915)

[Congcong Cai via cfe-commits]

HerrCai0907 wrote:

### Merge activity

* **Jan 17, 8:44 AM EST**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/122915).


https://github.com/llvm/llvm-project/pull/122915