upgrade to non-deprecated version of actions/cache

Author: melissag-ensemble

.github/workflows/deploy.yml

@@ -111,7 +111,7 @@ jobs:
           cmd: install
 
       - name: Gatsby Cache
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: |
             public
@@ -215,7 +215,7 @@ jobs:
           cmd: install
 
       - name: Gatsby Cache
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         with:
           path: |
             public