[Java][resttemplate] Enable access token refresh

[kota65535]

• Partially fix: [REQ][Java] Support refreshing access tokens  #16059

  • This PR fixes for clients with resttemplate library
  • If the design is OK, I'm willing to contribute for other libraries as well

• Added a function to set the access token supplier function

• We can verify the expiration of the access token in the supplier and then refresh it if needed

• To Java technical committee: @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

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[wing328]

@kota65535 thanks for the PR. From what I can tell it's not a breaking change. Please correct me if I'm wrong.

[kota65535]

@wing328 Yes, the ApiClient#setBearerToken(String) will work as before.

[wing328]

Thanks for the PR, which has been merged.

If the design is OK, I'm willing to contribute for other libraries as well

Yes please :)