fix(go/plugins/googlegenai): Update gemini models

[leixiaotian1]

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• linking to an issue that includes more details 3142

Checklist (if applicable):

• PR title is following https://www.conventionalcommits.org/en/v1.0.0/
• Tested (manually, unit tested, etc.)
• Docs updated (updated docs or a docs bug required)

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[timcreatedit]

Edit: tried this and it works for me!