Update Java Dependencies to Java 17

[mosoriob]

We are currently using an older version of Java, and @cweedall propose that we update our project's Java dependencies to Java 17. This upgrade will allow us to take advantage of the latest language improvements, performance enhancements, and security fixes.

[mosoriob]

The current version of OBA supports Java 11, 17, and 21. I'm unsure if dropping support for Java 11 is a good idea.

cc: @cweedall

[cweedall]

Apologies! I was caught up with making changes and had not realized you were actively maintaining the issues (and also somehow missed the notification that you CCed me!). I will make sure to look here more regularly.

As you probably noticed, I ended up bumping it back down to version 11. I kept the current major LTS versions for building (i.e. 11, 17, and 21) at present.

To be honest, my main concern is that Oracle makes it hard for regular users to recognize that you can get Java versions above 8. Even when you know that higher versions are available, it can be difficult to figure out where to download from. I have been working more in Node/Typescript/JS and C# until recently and had difficulty!

This is why I thought it would be good to include info in the README to help point individuals to the right place.

All this in mind - I think we could probably stay on Java 11 for the foreseeable future.