[compiler-rt] fix(compiler-rt/**.py): fix invalid escape sequences (PR #94030)

[Florian Mayer via llvm-commits]

https://github.com/fmayer approved this pull request.

verified that LHS equals RHS in python 3.11

```
>>> "^(.*) \(in (.*)\) \((.*:\d*)\)$" == r"^(.*) \(in (.*)\) \((.*:\d*)\)$",
(True,)
>>> "^(.*) \(in (.*)\) \((.*:\d*)\)$" == r"^(.*) \(in (.*)\) \((.*:\d*)\)$"
True
>>> "^( *#([0-9]+) *)(0x[0-9a-f]+) *(?:in *.+)? *\((.*)\+(0x[0-9a-f]+)\)" == r"^( *#([0-9]+) *)(0x[0-9a-f]+) *(?:in *.+)? *\((.*)\+(0x[0-9a-f]+)\)"
True
>>> (r'.*?(0x[0-9a-f]+):' + '([ ]*[\[ ][0-9a-f][0-9a-f]\]?)') ==  ( 
KeyboardInterrupt
>>> (r'.*?(0x[0-9a-f]+):' + '([ ]*[\[ ][0-9a-f][0-9a-f]\]?)' * 16) == (r'.*?(0x[0-9a-f]+):' + r'([ ]*[\[ ][0-9a-f][0-9a-f]\]?)' * 16)
True
>>> 
```

https://github.com/llvm/llvm-project/pull/94030