[NFC] Change lit test for print-changed=dot-cfg to use regular expression

Summary:

Issue 55761:
Change the lit test for print-changed=dot-cfg to have a regular expression
for the template arguments portion of the name for a pass manager pass.
This part of the name can change because it is based on the name provided
by the compiler, which is implementation-dependent. This mimics the
other change printer tests.

Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: mgorny (Michal Gorny)
Differential Revision: https://reviews.llvm.org/D126876