[llvm] [llvm-lit][test] Precommit tests for lit's built-in cat command (PR #101530)

[James Henderson via llvm-commits]

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@@ -0,0 +1,36 @@
+## Tests to check cat -e output
----------------
jh7370 wrote:

```suggestion
## Tests to check cat -e output.
```
Nit here and throughout: comments should end with a ".".

I think it would also be useful to include a brief description of what -e means.

https://github.com/llvm/llvm-project/pull/101530