[CIR] Workaround issue with clang-tidy unit tests

Disable them for good until we have a solution, this affecting GitHub CI jobs
and might get fixed once we rebase next. To reproduce the original issue: on a
Linux machine run `ninja check-clang-tools`.

#1836

Author: bcardosolopes

clang-tools-extra/unittests/CMakeLists.txt

@@ -11,4 +11,5 @@ add_subdirectory(clang-doc)
 add_subdirectory(clang-include-fixer)
 add_subdirectory(clang-move)
 add_subdirectory(clang-query)
-add_subdirectory(clang-tidy)
+# Workaround https://github.com/llvm/clangir/issues/1836
+# add_subdirectory(clang-tidy)