Remove vim.lang from syntax

[wxtim]

Point users of Cylc Get Resources to the new cylc.vim plugin.

closes #5626 .

Is probably massive overkill.

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg (and conda-environment.yml if present).
• Small change to peripheral script.
• Changelog entry included if this is a change that can affect users
• Self documenting
• Deprecation, raised against master

[oliver-sanders]

LGTM, the tests are failing as this file was used as a reference test (just pick a new file to test with).

I think this file may also have been used for:

• The "build" test on GH actions.
• Conda Forge release testing.

[wxtim]

I think this file may also have been used for:

* The "build" test on GH actions.

Can't see any evidence of this

* Conda Forge release testing.

Looks like it's using job.sh - which is so central to Cylc that it's probably a much better choice - https://github.com/conda-forge/cylc-flow-feedstock/blob/8e01cc9c760441929cc0a54ef1ac3205b5416451/recipe/meta.yaml#L36

[oliver-sanders]

Would be good to cover that CylcError line.

[hjoliver]

Not sure "deprecated" is right here, as you have essentially obsoleted the file.