Tests: Teach RunCMake to ignore lld-link PDB item index warnings

In commit fade5b5b8c (gitlab-ci: Update Windows builds to MSVC 19.31
toolset, 2022-03-09, v3.23.0-rc3~4^2~1) we switched from MSVC toolset
version 14.30.30705 to version 14.31.31103.  The latter causes the
Clang 13.0.0 lld-link tool to warn about invalid PDB item indexes, as
discussed [here](https://developercommunity.visualstudio.com/t/1667797).

This causes the RunCMake.PrecompileHeaders test PchLibObjLibExe case to
fail on NMake builds due to unexpected content on stderr.  The warnings
appear with Ninja too, but `ninja` prints them on stdout.  Teach the
RunCMake infrastructure to ignore these warnings.

Tests/RunCMake/RunCMake.cmake

@@ -153,6 +153,7 @@ function(run_cmake test)
     "|BullseyeCoverage"
     "|[a-z]+\\([0-9]+\\) malloc:"
     "|clang[^:]*: warning: the object size sanitizer has no effect at -O0, but is explicitly enabled:"
+    "|lld-link: warning: procedure symbol record for .* refers to PDB item index [0-9A-Fa-fx]+ which is not a valid function ID record"
     "|Error kstat returned"
     "|Hit xcodebuild bug"
     "|Recompacting log\\.\\.\\."