upgrade gson to 2.9.0

[lxning]

Description

Please include a summary of the feature or issue being fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes #(issue)
https://github.com/pytorch/serve/security/dependabot/20

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Feature/Issue validation/testing

Please describe the tests [UT/IT] that you ran to verify your changes and relevant result summary. Provide instructions so it can be reproduced.
Please also list any relevant details for your test configuration.

• Test A

• Test B

• Logs
  sanity.txt

Checklist:

• Have you added tests that prove your fix is effective or that this feature works?
• Has code been commented, particularly in hard-to-understand areas?
• Have you made corresponding changes to the documentation?
• Did you enable pre-commit to check and format your changes before pushing your changes?

[maaquib]

FYI: changes to serving-sdk require uploading the new build artifacts to the maven repo