[New msys2-runtime-package version] msys2-runtime: fix deadlock in pcon teardown (#6302)

```
msys2-runtime: fix deadlock in pcon teardown (#6302)

See https://github.com/msys2/msys2-runtime/pull/339

also includes some fixes for new build issues, see:
https://github.com/msys2/msys2-runtime/pull/340
```

https://github.com/msys2/MSYS2-packages/commit/b3f49ffd8d78f9f3e6518144ef6b3bd40a830e69