[llvm] [mlir] [CMake] add `SKIP` to `add_lit_testsuites` (PR #157176)

[Maksim Levental via llvm-commits]

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@@ -247,4 +247,5 @@ add_lit_testsuite(check-mlir "Running the MLIR regression tests"
 
 add_lit_testsuites(MLIR ${CMAKE_CURRENT_SOURCE_DIR}
   DEPENDS ${MLIR_TEST_DEPENDS}
+  SKIP python
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makslevental wrote:

nothing? there will be no `string(FIND ${lit_suite} ${skip} is_skip); is_skip > -1` and so no subdirs will be skipped.

https://github.com/llvm/llvm-project/pull/157176