dishaprakash 4e7b8a01b5 chore: Update model in Go Quickstart tests (#1631) ...

## Description

---
Updating the Gemini model from 1.5-flash to 2.0-flash in the Go
Quickstart tests for LangChain and Genkit samples.

This PR fixes the failing tests in
https://github.com/googleapis/genai-toolbox/pull/1572

## PR Checklist

---
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- [x] Make sure you reviewed

[CONTRIBUTING.md](https://github.com/googleapis/genai-toolbox/blob/main/CONTRIBUTING.md)
- [ ] Make sure to open an issue as a

[bug/issue](https://github.com/googleapis/genai-toolbox/issues/new/choose)
before writing your code! That way we can discuss the change, evaluate
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- [x] Ensure the tests and linter pass
- [x] Code coverage does not decrease (if any source code was changed)
- [x] Appropriate docs were updated (if necessary)
- [x] Make sure to add `!` if this involve a breaking change

🛠️ Fixes #<issue_number_goes_here>

2025-10-06 09:59:52 +05:30

..

en

chore: Update model in Go Quickstart tests (#1631)

2025-10-06 09:59:52 +05:30