Change library version to major minor hotfix

[de-jcup]

Situation

With version 1.0 only the pom files are available at https://mvnrepository.com/artifact/de.jcup.sarif.java/sarif-2.1.0/1.0 but no jar files (or signed jar files at all).

It is not possible to change a published maven central artifact! See https://central.sonatype.org/faq/can-i-change-a-component/#question

Here a problem become visible: We had only {major}.{minor} inside the version.
But a release build can (and this happend in 1.0) have bigger problems. But we could only provide a 1.1 with same feature set as before when we remain on the version handling.

It is a little bit odd to release a version with minor version changes when it's only bug fix release (hotfix)

Wanted

Describe inside documentation (README file) that we will have also a hotfix version part.
Always use milestones (and release versions) with semantic versioning after this.