Remove the mapping of maven artifacts at the injection-phase

[laeubi]

Some context here:

• https://github.com/eclipse/xtext-eclipse/issues/1931#issuecomment-1313985215
• https://github.com/eclipse-tycho/tycho/issues/1662

Currently we try to "guess" if a P2 dependency is actually a maven dependency from the P2 data, but actually this is only valid for "true" dependencies produced by the maven-target-location. As this always creates confusion and problems, we should remove this feature with Tycho 4.x, as it contains much better ways to archive such goals:

1. Consuming dependencies from maven-target locations directly whenever possible, we can use the target-inclusion for cases where one likes to "share" such items, copy them from one place to another (usually maven > p2-site) simply do not scale, as we can never be sure that this is also available to the build.
2. With the upcoming new resolver, declaring dependencies even in the pom become much easier and consistent (no more pom-dependencies=consider required!)
3. The mapping of P2 > "true maven" in the consumer-pom phase has shown to be much more flexible and reliable than anything we could have archiving with the current approach, for example we can easily configure this and even customize the outcome even more with standard maven techniques.