Remove GHA REST CI. (#5061)

The authentication for GHA REST CI job has expired causing recent
failures. REST CI was migrated to GitLab in #4740, so this PR removes
running REST CI on GHA.

The GHA REST CI job only runs on push (merge) to `dev` or release
branches so I merged on my fork to kick off a full CI run without this
job to test.


https://github.com/shaunrd0/TileDB/actions/runs/9451126638/job/26031334343

[sc-49272]

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TYPE: NO_HISTORY
DESC: Remove GHA REST CI.

Co-authored-by: KiterLuc <[email protected]>