[787] Add maven wrapper for consistent builds

[the-other-tim-brown]

What is the purpose of the pull request

Closes #787

• Adds a maven wrapper for consistent builds. This also allows users to build the project without installing maven themselves

Brief change log

• Maven wrapper is generated with version 3.9.11
• Docs are updated to reference the wrapper for consistency between environments and make the setup process easier

Verify this pull request

• If CI passes, we know the change is having the intended effect

[vinishjail97]

https://github.com/apache/incubator-xtable/blob/main/Dockerfile#L25
https://github.com/search?q=repo%3Aapache%2Fincubator-xtable%20mvn&type=code
There are few files that have been missed...do we want to follow the same style across the repo or left out for any reason?

[the-other-tim-brown]

https://github.com/apache/incubator-xtable/blob/main/Dockerfile#L25 https://github.com/search?q=repo%3Aapache%2Fincubator-xtable%20mvn&type=code There are few files that have been missed...do we want to follow the same style across the repo or left out for any reason?

@vinishjail97 there is one place I am unsure about: deploy_staging_jars - Can you suggest how to update the $MVN part?

[vinishjail97]

https://github.com/apache/incubator-xtable/blob/main/Dockerfile#L25 https://github.com/search?q=repo%3Aapache%2Fincubator-xtable%20mvn&type=code There are few files that have been missed...do we want to follow the same style across the repo or left out for any reason?

@vinishjail97 there is one place I am unsure about: deploy_staging_jars - Can you suggest how to update the $MVN part?

We can use MVN=${MVN:-./mvnw} in the beginning of the script verified it works locally.