Update maven wrapper

[kuhnroyal]

• ran mvn -N io.takari:maven:0.7.7:wrapper
• this fixes colored output not working in zsh/MacOs/BigSur, not exactly sure what caused it not to work anymore

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• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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[wing328]

Tested locally and the result is good.

[INFO] 
[INFO] --- spring-boot-maven-plugin:2.2.9.RELEASE:repackage (default) @ openapi-generator-online ---
[INFO] Replacing main artifact with repackaged archive
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary for openapi-generator-project 5.0.1-SNAPSHOT:
[INFO] 
[INFO] openapi-generator-project .......................... SUCCESS [ 26.006 s]
[INFO] openapi-generator-core ............................. SUCCESS [01:07 min]
[INFO] openapi-generator (core library) ................... SUCCESS [19:35 min]
[INFO] openapi-generator (executable) ..................... SUCCESS [ 50.135 s]
[INFO] openapi-generator (maven-plugin) ................... SUCCESS [ 36.004 s]
[INFO] openapi-generator-gradle-plugin (maven wrapper) .... SUCCESS [  2.277 s]
[INFO] openapi-generator-online ........................... SUCCESS [ 54.911 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  23:38 min
[INFO] Finished at: 2021-01-04T11:53:19+08:00
[INFO] ------------------------------------------------------------------------