Update java 11 version or let user specify exact version

I get a java jdk 11.0.2(requesting -openjdk11) which is by far not the newest and it results in a lot of issues because I have to deal with java bugs that are fixed already. Please let the user specify what java version they want like the proper version e.g. 11.0.7.

I am using this workaround to at least have 11.0.6 (on dist: bionic): https://github.com/vackosar/gitflow-incremental-builder/blob/master/.travis.yml#L85-L92

But yeah, there should be an explicit option for that.

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