chore: remove risingwavepodtemplate's crd file and webhook definitions

[arkbriar]

What's changed and what's your intention?

PLEASE DO NOT LEAVE THIS EMPTY !!!

Please explain IN DETAIL what the changes are in this PR and why they are needed:

• As title.

Checklist

• I have written the necessary docs and comments
• I have added necessary unit tests and integration tests

Refer to a related PR or issue link (optional)

[codecov]

Codecov Report

Merging #506 (6080e2c) into main (22d1bbd) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #506   +/-   ##
=======================================
  Coverage   67.74%   67.74%           
=======================================
  Files          27       27           
  Lines        4263     4263           
=======================================
  Hits         2888     2888           
  Misses       1325     1325           
  Partials       50       50           

Flag	Coverage Δ
unittests	67.74% <ø> (ø)

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Files Changed	Coverage Δ
pkg/metrics/metrics.go	61.42% <ø> (ø)

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