Fix wrong order, or redundant try/await in generated code which caused warnings

[amanthatdoescares]

Fixes #471
&
Fixes #470.

The JNI Swift generator emitted await try for async throwing calls,
which produces Swift compiler warnings. This change ensures try await
is emitted correctly.

[ktoso]

Appreciate the attempt but if you ran swift test you'd notice this isn't correct and is adding try even to methods which don't need it. Please run tests to verify your fixes are actually complete

[ktoso]

I took a stab at fixing this up, thanks for picking up the topic!

Next time please do run the tests locally and follow up to ensure they're passing 🙏

[amanthatdoescares]

@ktoso Thanks for jumping in and fixing it — I appreciate you taking the time.
Apologies for not running the tests locally before pushing; that’s on me.
I’ll make sure tests are run and verified next time so the contribution is solid and mistake-free. Thanks again for the guidance.

[ktoso]

No worries, thanks! Looking forward to more contributions :-)