feat: Improve the matching of required versions

[nielsbasjes]

@cstamas Followup of this discussion on Slack https://the-asf.slack.com/archives/C7Q9JB404/p1773056234905829?thread_ts=1773053661.648449&cid=C7Q9JB404

When people write in (for example) the maven-invoker-plugin something like invoker.toolchain.jdk.version = 11 it is implemented as an exact match on the mentioned version specified in the toolchains.xml .
Historically people would write this config manually and then the exact version 11 works as expected.

With the automatic generation of the toolchains.xml more places will contain the full version of the JDK like <version>11.0.29</version> instead of the more simple <version>11</version>.

The effect of people using these automatically generated toolchains.xml files is that now things still work as designed, but not as expected.

This is a quick implementation of my proposal to simply treat the requirement of a single number X as "the major version must be X".
I have also included the same for a "major.minor" requirement to accept all patch versions under that also.

This means a change from a mismatch to a match in cases like this:

matcher = RequirementMatcherFactory.createVersionMatcher("1.5.2");
matcher.matches("1.5");

I'm unsure if this change is "too breaking" to be implemented.

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[cstamas]

Take a peek at "counter pr" #11786