Bump libs/glfw from b35641f to 21fea01

Bumps [libs/glfw](https://github.com/glfw/glfw) from `b35641f` to `21fea01`.
- [Release notes](https://github.com/glfw/glfw/releases)
- [Commits](glfw/glfw@b35641f...21fea01)

---
updated-dependencies:
- dependency-name: libs/glfw
  dependency-type: direct:production
...

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