[llvm] github: Add tablegen directories to PR autolabeler (PR #109129)

[Aiden Grossman via llvm-commits]

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@@ -1008,3 +1008,8 @@ bazel:
 
 offload:
   - offload/**
+
+tablegen:
+  - llvm/include/TableGen/**
+  - llvm/lib/TableGen/**
+  - llvm/utils/TableGen/**
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boomanaiden154 wrote:

Do you want to include `llvm/test/TableGen` and `llvm/unittests/TableGen`?

https://github.com/llvm/llvm-project/pull/109129