feat: Update closed documentation process

[ADubhlaoich]

Proposed changes

This pull request updates the closed documentation contribution process by fixing the remote git command, and grouping the relevant a user would likely do in quick succession.

It also rephrases it on the premise that the user likely already has the main repository cloned, so gives and frames adding the remote as an earlier step in the process overall.

The process itself was used to make this pull request!

Checklist

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• I have read the contributing guidelines
• I have signed the F5 Contributor License Agreement (CLA)
• I have rebased my branch onto main
• I have ensured my PR is targeting the main branch and pulling from my branch from my own fork
• I have ensured that the commit messages adhere to Conventional Commits
• I have ensured that documentation content adheres to the style guide
• If the change involves potentially sensitive changes¹, I have assessed the possible impact
• If applicable, I have added tests that prove my fix is effective or that my feature works
• I have ensured that existing tests pass after adding my changes
• If applicable, I have updated README.md and CHANGELOG.md

Footnotes

1. Potentially sensitive changes include anything involving code, personally identify information (PII), live URLs or significant amounts of new or revised documentation. Please refer to our style guide for guidance about placeholder content. ↩

[github-actions]

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