Do not pnpm install for retag workflow (#1236)

Author: jakebailey

.github/workflows/update-ts-version-tags.yml

@@ -42,8 +42,6 @@ jobs:
     - run: pnpm install
     - run: pnpm build
     - run: git clone --depth 1 https://github.com/DefinitelyTyped/DefinitelyTyped ../DefinitelyTyped
-    - run: pnpm install
-      working-directory: ../DefinitelyTyped
     - name: retag
       run: node packages/retag/dist/index.js --path ../DefinitelyTyped
       env: