Integrate Maven Wrapper into the Debezium repos

In a project that uses Maven and often changes the required version, it might be easier to use Maven Wrapper (https://maven.apache.org/wrapper/) which allows you to pin the Maven version and lets users run Maven commands as usual by using ./mvnw which will download the right version of Maven automatically and execute with it.

We use the Gradle wrapper in all of our projects to great effect, it's nice that Maven has this option officially supported as well.

I will attach a PR but the relevant files can be generated with the command:

mvn wrapper:wrapper -Dmaven=3.8.4