chore(contracts-testing): force clearing cache

Github Actions don't allow clearing the cache right now, it is planned for end of 2022, this is to force a cache miss and workaround the limitation: actions/cache#2

Author: jaybuidl

.github/workflows/contracts-testing.yml

@@ -28,7 +28,7 @@ jobs:
         path: | 
           ~/.npm
           **/node_modules
-        key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/package-lock.json', '**/yarn.lock') }}
+        key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ secrets.CACHE_VERSION }}-${{ hashFiles('**/package-lock.json', '**/yarn.lock') }}
         restore-keys: |
           ${{ runner.os }}-build-${{ env.cache-name }}-
           ${{ runner.os }}-build-