Feature/issue 669 update all deps

[artoonie]

Note: this PR is based on #877 and the comments there apply. Closes #669.

The commits here:

1. Update plugins
2. Update code for latest spotbugs
3. Merge develop
4. Final fixes
5. Additional changes during Code Review

There is a warning about a deprecation when compiling now. We'll have to live with it -- it's caused by org.javamodularity:moduleplugin:1.8.12 which is a transitive dependency of org.openjfx.javafxplugin:org.openjfx.javafxplugin.gradle.plugin:0.0.14 which we cannot upgrade without moving to JDK 22, which is not LTS.

I also had to change org.junit.jupiter:junit-jupiter-engine from testRuntime to testImplementation, not fully sure why, something about java or gradle or something being stricter? Would love a second opinion on the consequences of that.

[yezr]

@HEdingfield can you approve again after I made the final commit? It was a minor one to fix a comment nit that had the unfortunate effect of dismissing your approval