go back to official release of yarn

.yarnrc.yml

@@ -1,9 +1,5 @@
 
-# !!!
-# We're running a custom-built version of yarn while waiting for this bugfix:
-# https://github.com/yarnpkg/berry/issues/2232#issuecomment-752052924
-# !!!
-yarnPath: .yarn/releases/yarn-sources.cjs
+yarnPath: .yarn/releases/yarn-2.4.1.cjs
 
 plugins:
   - path: .yarn/plugins/@yarnpkg/plugin-version.cjs