[chore] Update to yarn 4 (#90)

Update to yarn 4 and use `masto-fe-standalone-woodpecker-build` container for builds.

Reviewed-on: https://codeberg.org/superseriousbusiness/masto-fe-standalone/pulls/90
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Co-committed-by: tobi <tobi.smethurst@protonmail.com>

package.json

@@ -230,5 +230,6 @@
     "Capfile|Gemfile|*.{rb,ruby,ru,rake}": "bundle exec rubocop --force-exclusion -a",
     "*.{js,jsx,ts,tsx}": "eslint --fix",
     "*.{css,scss}": "stylelint --fix"
-  }
+  },
+  "packageManager": "yarn@4.10.3"
 }