[CELEBORN-218][HELM] Move helm chart to dedicated directory

[zwangsheng]

What changes were proposed in this pull request?

According to those following: we should move ./docker/helm => ./charts/celeborn

Why are the changes needed?

The changes are needed to be compliant with Helm recommendations:

https://helm.sh/docs/topics/charts/#the-chart-file-structure

The directory name is the name of the chart (without versioning information).
Thus, a chart describing WordPress would be stored in a wordpress/ directory.

https://helm.sh/docs/howto/chart_releaser_action/#repository-changes

The charts should be placed under /charts directory at the top-level of the directory tree.

Also according to apache/kyuubi#4034

Does this PR introduce any user-facing change?

How was this patch tested?

[codecov]

Codecov Report

Merging #1160 (a908249) into main (810a8d0) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main    #1160   +/-   ##
=========================================
  Coverage     26.88%   26.88%           
  Complexity      747      747           
=========================================
  Files           200      200           
  Lines         17022    17022           
  Branches       1838     1838           
=========================================
  Hits           4574     4574           
  Misses        12151    12151           
  Partials        297      297           

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[waitinfuture]

LGTM, thanks!