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

[James Henderson via llvm-commits]

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@@ -1,25 +1,30 @@
-# Check that internal env can call internal env.
+## Tests env command's handling of nested calls, setting, unsetting, and variable retention.
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jh7370 wrote:

Based on the file name and what the test cases actually do, I think this comment should say "Tests the behaviour of chaining env commands together." Or something to that effect anyway.

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