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

[via llvm-commits]

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@@ -1,4 +1,4 @@
-## Tests the env command's ability to handle setting, unsetting, and mixing environment variables.
+## Tests the env command in various scenarios: without arguments, setting, unsetting, and mixing envrionment variables. 
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Harini0924 wrote:

Done. 

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