[language-java] Support highlighting of multiline strings

[ditpowuh]

Thanks in advance for your bug report!

• Have you reproduced issue in safe mode?
• Have you used the debugging guide to try to resolve the issue?
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• Have you checked to make sure your issue does not already exist?
• Have you checked you are on the latest release of Pulsar?

What happened?

Text blocks (standard from Java 15 and above) have yet to be added into the in-built 'language-java' package.

Pulsar version

v1.130.1

Which OS does this happen on?

🪟 Windows

OS details

Windows 11

Which CPU architecture are you running this on?

64-bit(x86_64)

What steps are needed to reproduce this?

1. Open/create Java file
2. Use a text block

Additional Information:

Screenshot:

[savetheclocktower]

Easy fix, and it allows me to clear an item from my to-do list. Thanks for the report!

#1377 addresses this and will probably make it into the next release.