Update GHA.

Author: digisomni

.github/workflows/deploy.yml

@@ -18,7 +18,8 @@ jobs:
         working-directory: website
         run: |
           npm ci
-          npm run build
+          npm install --global yarn
+          yarn install
 
       # Popular action to deploy to GitHub Pages:
       # Docs: https://github.com/peaceiris/actions-gh-pages#%EF%B8%8F-docusaurus

.github/workflows/test-deploy.yml

@@ -18,4 +18,5 @@ jobs:
         working-directory: website
         run: |
           npm ci
-          npm run build
+          npm install --global yarn
+          yarn install