Update github actions/cache@v3

Author: kipcole9

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
           otp-version: ${{matrix.pair.otp}}
           elixir-version: ${{matrix.pair.elixir}}
 
-      - uses: actions/cache@v2
+      - uses: actions/cache@v3
         with:
           path: |
             deps