Load all models including targz

[m10an]

Description

Fixes #3320

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Feature/Issue validation/testing

ran torchserve_sanity.py and regression_tests.py

Checklist:

• Did you have fun?
• Have you added tests that prove your fix is effective or that this feature works?
• Has code been commented, particularly in hard-to-understand areas?
• Have you made corresponding changes to the documentation?

I haven't found any tests related testing load_models=all parameter in order to add case for tar.gz. Maybe I missed, or maybe it worth to create one, but not sure which place is most appropriate for this type of test (frontend test, pytest?).

[m10an]

regression_logs.txt

[mreso]

LGTM, thanks for contributing!