[bazel] Add mlir/utils/generate-test-checks.py to bazel overlay (llvm#160693)

Author: TomMurray

utils/bazel/llvm-project-overlay/mlir/BUILD.bazel

@@ -8,6 +8,7 @@
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
 load("@bazel_skylib//rules:expand_template.bzl", "expand_template")
 load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library")
+load("@rules_python//python:defs.bzl", "py_binary")
 load("//llvm:targets.bzl", "llvm_targets")
 load(
     ":build_defs.bzl",
@@ -14428,3 +14429,8 @@ cc_library(
         "//llvm:Support",
     ],
 )
+
+py_binary(
+    name = "generate-test-checks",
+    srcs = ["utils/generate-test-checks.py"],
+)