Fix local test test_saving_remote fail

[Mecoli1219]

Tracking issue

flyteorg/flyte#5687

Why are the changes needed?

get_and_save_remote_with_click_context(...) will call get_remote(cfg_file_location, ...), which will call get_config_file if the first argument is None.
As described in #2705, get_config_file will not always return None in developers' local environments.

What changes were proposed in this pull request?

Add a mock function that forces the return value of get_config_file to None.

How was this patch tested?

make unit_test

Setup process

Run it locally

Screenshots

I'll open other PRs to fix the other 2 unit tests.

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Related PRs

#2705
#2706

Docs link