[MNT] Swapped tensorflow and pytorch to install only CPU version

[chrisholder]

Reference Issues/PRs

#2415

What does this implement/fix? Explain your changes.

This PR adds a custom github action when installing all_extras on ubuntu. The custom action installs tensorflow-cpu and pytorch cpu instead of the "normal" version which comes with all the GPU code. By installing the CPU version it saves considerable install time but in addition saves a considerable amount of RAM usage during the test running (as the package sizes are dramatically smaller). This should help to prevent issues causing the CI to crash due to exceeding memory limits.

Does your contribution introduce a new dependency? If yes, which one?

Any other comments?

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[chrisholder]

Do not merge this yet need to get rid of the additional periodic test which I turned on just for this branch.

[chrisholder]

This file will be removed before merging into main. Just for testing.