[Index] Un-XFAIL test with msan

Passing after #127078.

Author: vitalybuka

clang/test/Index/comment-to-html-xml-conversion.cpp

@@ -20,7 +20,6 @@
 // RUN: FileCheck %s < %t/out.c-index-direct
 // RUN: FileCheck %s < %t/out.c-index-pch
 
-// XFAIL: msan
 // XFAIL: valgrind
 
 #ifndef HEADER