Fix #47355: num_experts fallback instead of override in GlmMoeDsaConfig
Author: shark8pepper-eng
Pull request: yes

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Fixes #47355.

# What does this PR do?

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Comments:
**[For maintainers]** Suggested jobs to run (before merge)

run-slow: glm_moe_dsa

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### CI recap

**Dashboard:** [View test results in Grafana](https://transformers-ci.lor-e.huggingface.cool/d/pytest-observability-by-pr/pytest-observability-branch?var-pr=47398)
**Latest run:** [29647532768](https://github.com/huggingface/transformers/actions/runs/29647532768)
**Result:** `failure` | Grafana metrics are not available yet.

> **Code quality check failed**: test jobs were skipped. Fix the code quality issues and push again to run tests.

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