Update source and target compatibility for java 21

[jowg-amazon]

Description

Update source and target compability to fix CI similar to what was done in notifications

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• [ ] New functionality includes testing.
• [ ] New functionality has been documented.
• [ ] API changes companion pull request created.
• [ ] Commits are signed per the DCO using --signoff.
• [ ] Public documentation issue/PR created.

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