Support cache clean policy

[cheyang]

Signed-off-by: cheyang cheyang@163.com

Ⅰ. Describe what this PR does

Ⅱ. Does this pull request fix one issue?

fixes #2526

Ⅲ. List the added test cases (unit test/integration test) if any, please explain if no tests are needed.

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[fluid-e2e-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[codecov]

Codecov Report

Merging #2527 (68c2b9d) into master (7c5661a) will increase coverage by 0.00%.
The diff coverage is 67.74%.

❗ Current head 68c2b9d differs from pull request most recent head 6b01e70. Consider uploading reports for the commit 6b01e70 to get more accurate results

@@           Coverage Diff           @@
##           master    #2527   +/-   ##
=======================================
  Coverage   67.55%   67.55%           
=======================================
  Files         367      368    +1     
  Lines       21267    21298   +31     
=======================================
+ Hits        14366    14387   +21     
- Misses       5218     5224    +6     
- Partials     1683     1687    +4     

Impacted Files	Coverage Δ
pkg/ddc/alluxio/transform_clean_cache_policy.go	66.66% <66.66%> (ø)
pkg/ddc/alluxio/transform.go	61.95% <100.00%> (+0.13%)	⬆️

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