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

[James Henderson via llvm-commits]

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@@ -1,3 +1,5 @@
+## Tests the env command's ability to handle setting, unsetting, and mixing environment variables.
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jh7370 wrote:

Please don't resolve comment threads I've started, even if you think you've addressed my comment. My comment was about the file name, which to me looks incorrect. What does "args-none" mean in the file name? `-u FOO` or whatever is not "no arguments".

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