Use raw strings for regular expressions
Per https://docs.python.org/3/whatsnew/3.12.html:
A backslash-character pair that is not a valid escape sequence now generates a
SyntaxWarning, instead of DeprecationWarning.
See https://github.com/python/cpython/issues/98401
The warnings without this change are:
attic/calc_tickadj/calc_tickadj:74: SyntaxWarning: invalid escape sequence '\d'
contrib/cpu-temp-log:60: SyntaxWarning: invalid escape sequence '\s'