Make build work with Java17

[cstamas]

In short: now build works on both, Java 11 and Java 17 (tested with 11 and 17 Temurin on Linux).

Also, build (plugins and tooling) is updated as well, dependencies are NOT touched except logging: they are set to slf4j 1.7.36 and logback 1.1.11. Reason is that (in tests) they were "crossed": slf4j 1.6 was used with 1.1.11 logback (while logback 1.1.x requires 1.7.x slf4j). So, dependencies can be set back (slf4j 1.6.x and logback 1.0.0) but then it needs to be consequently set (target AND test POM).

Changes:

• align POM with CONTRIBUTING (enforce Java11), up Maven requirement to 3.8.4+
• use javac release=7 flag (instead of source/target+sniffer), remove animal sniffer
• fix enforcer override (was not working, as parent POM defined it in plugin not pluginMgmt section)
• move all plugin versions to top level POM
• update to latest plugins

Java 17 changes (commit 8fa9020c2faa5b7c1603e62e74668a64c4a69032):

• update felix and tycho versions to latest
• surefire: fixate junit47 provider, as presence of testng on classpath confuses surefire
• align PDE and POM declared logging lib versions (slf4j, logback), it caused clashes
• tests: exclude org.osgi:org.eclipse.osgi as it clashes (on test classpath) with felix
• tests: pass guiceVersion to UTs to be able to create "assumptions"
• ExampleTestCase testContainerLookup UT fails on Java 17 + Guice4 (did not look deeper), is disabled on that combo

[cstamas]

Frankly, I'd drop this PR and rather continue with https://github.com/eclipse/sisu.inject/pull/71 that incorporates this one as well....

[cstamas]

Superseded by https://github.com/eclipse/sisu.inject/pull/71