[llvm] [bazel] Fix testonly declarations in mlir (PR #195159)

[Alex Trotta via llvm-commits]

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@@ -538,7 +550,6 @@ def gentbl_sharded_ops(
         gentbl_shard_rule(
             index = i,
             name = name + "__src_shard" + str(i),
-            testonly = test,
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Ahajha wrote:

:facepalm: yea that's actually it, thanks. one more update incoming, should be the last one

https://github.com/llvm/llvm-project/pull/195159