Add marshalparser to Python tests

Marshalparser helps us to uniform byte-compiled Python files
so it has to be able to also parse pyc files from
the main python packages.
Moreover, it has its own database of magic numbers so this test
checks that the parser is compatible with the latest python before
we ship it.

tests.yml

@@ -58,6 +58,9 @@
     - debugflags:
         dir: flags
         run: python3-debug ./assertflags.py -Og
+    - marshalparser_compatibility:
+        dir: marshalparser
+        run: SAMPLE=10 test_marshalparser_compatibility.sh
     required_packages:
     - dnf
     - gcc
@@ -79,3 +82,4 @@
     - python3-test
     - python3-debug
     - python3-rpm-macros
+    - marshalparser