Add corepack enable to yml

Author: thatblindgeye

.github/workflows/pr-preview.yml

@@ -7,7 +7,7 @@ jobs:
       SURGE_LOGIN: ${{ secrets.SURGE_LOGIN }}
       SURGE_TOKEN: ${{ secrets.SURGE_TOKEN }}
       GH_PR_TOKEN: ${{ secrets.GH_PR_TOKEN }}
-      GH_PR_NUM:   ${{ github.event.number }}
+      GH_PR_NUM: ${{ github.event.number }}
     steps:
       - uses: actions/checkout@v2
       # Yes, we really want to checkout the PR
@@ -24,6 +24,7 @@ jobs:
       - uses: actions/setup-node@v1
         with:
           node-version: '18'
+      - run: corepack enable
       - uses: actions/cache@v4
         id: yarn-cache
         name: Load npm deps from cache