Review "Running MaxText via Pathways" guide

[melissawm]

Description

Follow-up to #2246

This PR includes minor fixes to the "Running MaxText via Pathways" guide, which can be seen as suggestions. If these are not useful, feel free to close.

Changes:

• Remove "Guide" from the title, to make this document title consistent with the other how-to guides in the documentation site.
• Break some of the bash commands to make them easily copy-pastable. In Review of "Running MaxText at Scale with XPK" guide #2267 , I suggest adding the sphinx-copybutton extension which adds a convenient button to all code-blocks, allowing readers to copy-paste these code blocks more easily. Removing comments and breaking the code-blocks makes it easier to execute these commands as a user.
• A few changes related to fixing the docs build (see Review Data Input Pipeline guides #2266 for context)

Tests

Documentation pages were successfully built locally.

Checklist

Before submitting this PR, please make sure (put X in square brackets):

• I have performed a self-review of my code.
• I have necessary comments in my code, particularly in hard-to-understand areas.
• I have run end-to-end tests tests and provided workload links above if applicable.
• I have made or will make corresponding changes to the doc if needed.

[khatwanimohit]

LGTM for changes to the pathways document

[github-actions]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed soon if no further activity occurs. Thank you for your contributions.

[github-actions]

This PR was closed because it has been inactive for a while. Please reopen it if you are still working on it.

[melissawm]

Hi all, not sure how to move this forward. Thanks