[llvm] [CI][Github] Enable CIR CI build and test (PR #147430)

[Aiden Grossman via llvm-commits]

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@@ -247,6 +255,15 @@ def _get_modified_projects(modified_files: list[str]) -> Set[str]:
         # capacity.
         if len(path_parts) > 3 and path_parts[:3] == ("llvm", "utils", "gn"):
             continue
+        # If the file is in the clang/lib/CIR directory, add the CIR project.
+        if len(path_parts) > 3 and (
+            path_parts[:3] == ("clang", "lib", "CIR")
+            or path_parts[:3] == ("clang", "test", "CIR")
+            or path_parts[:4] == ("clang", "include", "clang", "CIR")
+        ):
+            modified_projects.add("clang")
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boomanaiden154 wrote:

I think it's probably cleaner to drop the `continue` and just fall through.

https://github.com/llvm/llvm-project/pull/147430