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](emscripten-core/setup-emsdk@v14...v15)

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

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -411,7 +411,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-      - uses: mymindstorm/setup-emsdk@v14
+      - uses: mymindstorm/setup-emsdk@v15
       - name: check emsdk
         run: emcc -v
       - name: build