Update build-docs.yaml

Author: Palbahngmiyine

.github/workflows/build-docs.yaml

@@ -12,8 +12,8 @@ jobs:
       uses: actions/checkout@v2
     - name: Build
       run: |
-        yarn install
-        yarn run docs
+        pnpm install
+        pnpm run docs
     - name: Commit and push docs
       working-directory: ./
       run: |