fix: remove guava

[i1619khz]

change

• remove guava
• replace guava's HashFunction with md5 function that only depends on jdk

test
Tests run: 126, Failures: 0, Errors: 0, Skipped: 0

Fix: #279

[CLAassistant]

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[casbin-bot]

@tangyang9464 @seriouszyx @elfisworking please review

[codecov-commenter]

Codecov Report

Merging #280 (061b1d3) into master (a21b219) will decrease coverage by 0.17%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master     #280      +/-   ##
==========================================
- Coverage   66.38%   66.20%   -0.18%     
==========================================
  Files          45       45              
  Lines        2240     2240              
  Branches      393      393              
==========================================
- Hits         1487     1483       -4     
- Misses        635      638       +3     
- Partials      118      119       +1     

Impacted Files	Coverage Δ
src/main/java/org/casbin/jcasbin/util/Util.java	63.73% <50.00%> (-4.40%)	⬇️

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[hsluoyz]

@i1619khz plz:

1. Use fix: xxx instead of refactor: xxx for PR title and commit msg.
2. Fix semantic-PR
3. Fix CLA

[hsluoyz]

@i1619khz plz don't close this PR. You can do the re-work inside this PR.

[hsluoyz]

@tangyang9464 plz review

[tangyang9464]

@i1619khz plz suqash your commits to fix semantic pr errror

[github-actions]

🎉 This PR is included in version 1.24.1 🎉

The release is available on:

• GitHub release
• v1.24.1

Your semantic-release bot 📦🚀