[Docs] Databricks Agent Doc

[Future-Outlier]

Describe your changes

Add agent service sample in Web APIs Databricks plugin.
Currently, we can enable flyteagent from flyte using helm.
We want to enable users to deploy the Datbabricks agent through Helm.

Here is the URL: https://flyte--4008.org.readthedocs.build/en/4008/deployment/agents/databricks.html#deployment-agent-setup-databricks

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Screenshots

Tracking Issue

#3936

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[Future-Outlier]

@pingsutw Please review, thanks a lot!

[Future-Outlier]

@pingsutw Please review, thanks a lot!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (ebed2a6) 59.40% compared to head (64b0a54) 59.40%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4008      +/-   ##
==========================================
- Coverage   59.40%   59.40%   -0.01%     
==========================================
  Files         638      638              
  Lines       53957    53957              
==========================================
- Hits        32052    32051       -1     
- Misses      19376    19377       +1     
  Partials     2529     2529              

Flag	Coverage Δ
unittests	59.40% <ø> (-0.01%)	⬇️

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