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

[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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Harini0924 wrote:

I'm sorry for the confusion. You're right; the name "args-none" doesn't accurately reflect the content of the test, especially since the file includes scenarios with arguments like `-u FOO` and others. A more suitable name could be something like `env-var-handling.txt` or `env-command-tests.txt` to broadly cover all the scenarios tested in the file. Do either of these work, or do you have any other suggestions?

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