scripts/pretty_print_stacks.py: Silence warning from Python 3.12

Python 3.12 complains:

 ./scripts/pretty_print_stacks.py:41: SyntaxWarning:
  invalid escape sequence '\?'
  m = re.match(b'(.*) at (.*):(([0-9]+)|\?)([^:]*)', line)

Switch to a raw byte string to silence the problem.

Message-ID: <20231219153134.47323-1-thuth@redhat.com>
Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

scripts/pretty_print_stacks.py

diff --git a/scripts/pretty_print_stacks.py b/scripts/pretty_print_stacks.py
index d990d30..a1526d5 100755
--- a/scripts/pretty_print_stacks.py
+++ b/scripts/pretty_print_stacks.py
@@ -38,7 +38,7 @@
         return
 
     for line in out.splitlines():
-        m = re.match(b'(.*) at (.*):(([0-9]+)|\?)([^:]*)', line)
+        m = re.match(rb'(.*) at (.*):(([0-9]+)|\?)([^:]*)', line)
         if m is None:
             puts('%s\n' % line)
             return