build(deps): bump mymindstorm/setup-emsdk from 14 to 15

Bumps [mymindstorm/setup-emsdk](https://github.com/mymindstorm/setup-emsdk) from 14 to 15.
- [Release notes](https://github.com/mymindstorm/setup-emsdk/releases)
- [Commits](https://github.com/mymindstorm/setup-emsdk/compare/v14...v15)

---
updated-dependencies:
- dependency-name: mymindstorm/setup-emsdk
  dependency-version: '15'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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