source: use import error

uses the more broad ImportError
instead of ModuleNotFoundError

reasoning being if some submodule
(the one I'm configuring currently is
my.twitter.twint) doesn't have additional
imports from another parser/DAL, but it
still has a config block, the user would
have to create a stub-config block in their
config to use the all.py file

my/core/source.py

@@ -43,7 +43,7 @@ def import_source(
             try:
                 res = factory_func(**kwargs)
                 yield from res
-            except ModuleNotFoundError:
+            except ImportError:
                 from . import core_config as CC
                 suppressed_in_conf = False
                 if module_name is not None and CC.config._is_module_active(module_name) is False: