[llvm] [llvm-lit] Print environment variables when using env without subcommand (PR #98414)

[via llvm-commits]

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@@ -1,32 +1,32 @@
-# Check default environment.
+## Check default environment.
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Harini0924 wrote:

I have added comments to the files I have modified. Is there anything else I should change?

https://github.com/llvm/llvm-project/pull/98414