Remove finalizer usage

the finalization mechanism is deprecated for removal. NetBeans is still using it occasionally.

Usage must be replaced with alternatives like for example the Java 9 [Cleaner API](https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/ref/Cleaner.html) where needed.

JEP: https://openjdk.org/jeps/421

there is a command line flag which simplifies testing during the transition period:
```
Finalization remains enabled by default in JDK 18.
A new command-line option --finalization=disabled disables finalization.
A JVM launched with --finalization=disabled will not run any finalizers — not even those declared within the JDK itself.
```

Start by searching the NetBeans sources for finalizer usage, then read JEP 421 and review the Java 9 Cleaner API as possible replacement guidance. Use --finalization=disabled to test the transition; done means the relevant usage has been replaced and NetBeans still works without finalization.

Written by the indexing model from the issue text.