Workbench: Install classic Yarn (v1).

workbench/Dockerfile

@@ -261,7 +261,7 @@ RUN npm install --global \
         corepack \
     && \
     chown -R root:root /usr/local/lib/node_modules/@bitwarden/cli/node_modules/ && \
-    corepack install --global yarn && \
+    corepack install --global yarn@1 && \
     rm -rf /tmp/* /var/tmp/* ~/.cache/*
 RUN export GOPATH=/usr/local/lib/go && \
     mkdir "$GOPATH" && \