[llvm] [llvm-lit][test][NFC] Moved cat command tests into separate lit test file (PR #102366)

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,83 @@
+# Check cat command with single file.
+#
+# RUN: rm -rf %T/testCat
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ilovepi wrote:

I know these are the existing test lines, but we’ve deprecated %T. Instead use %t. I think you also probably do need the testCat subdirectory either. 

https://github.com/llvm/llvm-project/pull/102366