Use raw strings for regular expressions with invalid escape sequences

If "T(\d*)" was "T(\n*)" it would search for newlines.  There isn't
any such \d escape character.

It should be "T(\\d*)" or r"T(\d*)" going with the latter, to be
easier to read and be consistent with other Cura usage.

Start python with -Wd or for python 3.12 will raise a SyntaxWarning.

plugins/PostProcessingPlugin/Script.py

@@ -122,7 +122,7 @@ class Script:
         if not key in line or (';' in line and line.find(key) > line.find(';')):
             return default
         sub_part = line[line.find(key) + 1:]
-        m = re.search('^-?[0-9]+\.?[0-9]*', sub_part)
+        m = re.search(r'^-?[0-9]+\.?[0-9]*', sub_part)
         if m is None:
             return default
         try: