[llvm] [lit] add --max-retries-per-test execution option (PR #141851)

[Konrad Kleine via llvm-commits]

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@@ -0,0 +1,23 @@
+# ALLOW_RETRIES: 3
+# RUN: "%python" "%s" "%counter"
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kwk wrote:

It would maybe be possible to share the test file across two of the tests that don't modify `ALLOW_RETRIES:` in the test file. But the test file is being used in several other places as well. And so I continued in that habit. 

https://github.com/llvm/llvm-project/pull/141851