[YUNIKORN-2503] Use internal annotation prefix for placeholder pod

[chenyulin0719]

What is this PR for?

Based on the design doc in YUNIKORN-1351 .

1. Remove label 'placeholder' in placeholder pod
2. Reanme placeholder's annotation to 'yunikorn.apache.org/placeholder' to 'internal.yunikorn.apache.org/placeholder'

(2024/03/30 Update eb274a458e3a431bc27b44a272f43bdc922317f6)

1. Support old placeholder metadata until v1.7.0.

What type of PR is it?

• [x] - Improvement

Todos

NA

What is the Jira issue?

https://issues.apache.org/jira/browse/YUNIKORN-2503

How should this be tested?

All existing e2e test should pass.

Screenshots (if appropriate)

Questions:

NA

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 71.80%. Comparing base (8be3910) to head (9b58d89).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #808   +/-   ##
=======================================
  Coverage   71.79%   71.80%           
=======================================
  Files          43       43           
  Lines        6351     6353    +2     
=======================================
+ Hits         4560     4562    +2     
+ Misses       1589     1588    -1     
- Partials      202      203    +1     

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 66.03%. Comparing base (1e4bcc0) to head (4844873).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #808      +/-   ##
==========================================
- Coverage   66.04%   66.03%   -0.01%     
==========================================
  Files          69       69              
  Lines        7537     7547      +10     
==========================================
+ Hits         4978     4984       +6     
- Misses       2347     2350       +3     
- Partials      212      213       +1     

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:loudspeaker: Have feedback on the report? Share it here.

[chenyulin0719]

Update to the latest codebase.

@chia7712 @brandboat Could I have your review?

[chia7712]

I guess we need a follow-up to update docs, right?

[chenyulin0719]

Yes. I will remove the internal placeholder label/annotation from user guide without any deprecated warning.
(Since we don't expect any users to be using the internal placeholder. )

• https://yunikorn.apache.org/docs/next/user_guide/labels_and_annotations_in_yunikorn