Added a new Workshop readme file and updated the main readme

[sdutta9]

Proposed changes

Added a single readme file that lists all the workshops under the NGINX Workshops subfolder instead of creating individual workshop folders.

Checklist

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• I have read the contributing guidelines.
• I have signed the F5 Contributor License Agreement (CLA).
• If applicable, I have added tests that prove my fix is effective or that my feature works.
• If applicable, I have checked that any relevant tests pass after adding my changes.
• I have updated any relevant documentation (README.md and/or CHANGELOG.md).

[Copilot]

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

README.md:56

• [nitpick] The workshop is referred to as 'NGINX One' in the main README, while the consolidated file uses 'NGINX One Console' in its table. Consider aligning these names for consistency.

|[NGINX One](nginx-workshops/README.md)|Learn everything you need to get started with NGINX One Console and its capabilities|@apcurrier, @chrisakker, @sdutta9|