invoke 2.1.3 does not work when run inside bash

Reproduce the issue with the shown tasks.py, tasks/init.py, tasks/build.py, and tasks/tests.py structure using both direct invocation and bash -c "invoke -l -d". Compare the loader output for each command, focusing on why the tasks.py module is selected in the shell case. Done means the defined tasks are discovered consistently in both invocation modes.

I have a typical folder structure with:

/tasks.py
/tasks/__init__.py
/tasks/build.py
/tasks/tests.py

Everything runes with 2.0.0, but after upgrading to 2.1.3 tasks are not found anymore.

When run invoke -l -d I get a working output:

invoke.program.parse_collection: No default namespace provided, trying to load one from disk
invoke.loader.find: FilesystemLoader find starting at '/Users/alexander.petermann/projects/abc'
invoke.loader.find: Found module: '/Users/alexander.petermann/projects/abc/tasks'
invoke.config._load_file: Didn't see any /Users/alexander.petermann/projects/abc/invoke.yaml, skipping.
....

but if I call invoke inside a bash script OR like bash -c "invoke -l -d", invoke will not find the defined tasks:

invoke.program.parse_collection: No default namespace provided, trying to load one from disk
invoke.loader.find: FilesystemLoader find starting at '/Users/alexander.petermann/projects/abc'
invoke.loader.find: Found module: ModuleSpec(name='tasks', loader=<_frozen_importlib_external.SourceFileLoader object at 0x1015fe1d0>, origin='/Users/alexander.petermann/projects/abc/tasks.py')
invoke.config._load_file: Didn't see any /Users/alexander.petermann/projects/abc/invoke.yaml, skipping.
...