Update JDK for CI build to 11

[Michael1993]

Closes #606

Proposed commit message:

${action} (${issues} / ${pull-request}) [max 70 characters]

${body} [max 70 characters per line]

${references}: ${issues}
PR: ${pull-request}

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PR checklist

The following checklist shall help the PR's author, the reviewers and maintainers to ensure the quality of this project.
It is based on our contributors guidelines, especially the "writing code" section.
It shall help to check for completion of the listed points.
If a point does not apply to the given PR's changes, the corresponding entry can be simply marked as done.

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• Site documentation in .adoc file references demo in src/demo/java instead of containing code blocks as text
• Only one sentence per line (especially in .adoc files)
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I hereby agree to the terms of the JUnit Pioneer Contributor License Agreement.

[beatngu13]

I wonder if we really want to move the SonarCloud analysis into the basic build. Before:

Now:

IIRC so far a failing SonarCloud analysis wouldn't stop following jobs, because it represents a separate branch in the workflow. This is now no longer the case I believe.

[Michael1993]

Yeah, I don't mind. I think we can commit to a stricter workflow.

[Bukama]

LGTM

[breun]

Does this mean JUnit Pioneer 1.7.0 won't be compatible with projects that use Java 8?

[Michael1993]

Does this mean JUnit Pioneer 1.7.0 won't be compatible with projects that use Java 8?

Hi, sorry, no, this is a bit misleading - this is only for builds. The code base is still Java 8 and should be compatible with any project using Java 8.

[breun]

Ok great for the quick response, thanks!

[beatngu13]

@breun FYI Pioneer 2.0 will likely use Java 11: #617