chore: [workflows] don't release from forks

Author: mweststrate

.github/workflows/release.yml

@@ -23,6 +23,8 @@ jobs:
       - name: build
         run: yarn build
       - name: publish
+        # avoid release on fork
+        if: github.repository == 'immerjs/immer'
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           NPM_TOKEN: ${{ secrets.NPM_TOKEN }}