Update "Java EE" language" in spec doc.

[scottkurz]

E.g.:

Java EE environments. It requires Java 6 or higher.

[ThomasVitale]

@scottkurz can I help with this task?

[scottkurz]

@ThomasVitale thanks for the offer.

Sure, in addition to the s/Java EE/Jakarta EE/ the "Java 6" statement also needs updating. The https://eclipse-ee4j.github.io/jakartaee-platform/jakartaee9/JakartaEE9ReleasePlan has a new requirement under "Java SE Version" that we should capture.

There's a point or two in #23 if you're interested in reviewing that too.

Thanks.

Though we might already have a separate issue

[ThomasVitale]

@scottkurz perfect, thanks, I'll start working on it.

[ThomasVitale]

@scottkurz I have opened a PR for this task and also looked at #23. I opened a separate PR for that, hope it's ok.

[ThomasVitale]

@scottkurz Since the PR has been merged, can this issue be closed?

[scottkurz]

Thx @ThomasVitale, closing.