tests: run all tests, but exclude tests specific to my computer from CI

controllable via HPI_TESTS_KARLICOSS=true

tests/rtm.py

@@ -1,6 +1,7 @@
-from my.rtm import all_tasks
+from .common import skip_if_not_karlicoss as pytestmark
 
 
-def test():
+def test() -> None:
+    from my.rtm import all_tasks
     tasks = all_tasks()
     assert len([t for t in tasks if 'gluons' in t.title]) > 0