[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:

Nearly there, but now I'm looking at the test file name. What is significant about the "none" part of the file name? I'd interpret it to mean "env with no args", but most of the test cases in this file have at least one argument.

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