Make Pytest log in color in Github Action

[eitanturok]

What does this PR do?

Currently, running pytest locally generates logs in color. But in Github Actions (GA), the logs are only in white. And it does not look so nice. Adding the flag

 --color=yes

causes pytest to log in color and makes things look nice again. This improves visibility and makes it easier on the eyes to see when tests fail/succeed.

I tested this flag on my fork of MegaBlocks but it should be the same here.

Without:
Here is a GA without the --color=yes flag:

With:
Here is a GA with the --color=yes flag:

What issue(s) does this change relate to?

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[karan6181]

LGTM