chore: change RPC_MAINNET URL

Author: nadir-akhtar

.github/workflows/foundry.yml

@@ -72,7 +72,7 @@ jobs:
           esac
         env:
           FOUNDRY_PROFILE: ${{ matrix.suite == 'Fork' && 'forktest' || 'medium' }}
-          RPC_MAINNET: https://billowing-capable-sound.quiknode.pro/
+          RPC_MAINNET: https://eth-mainnet.g.alchemy.com/v2/demo
 
   # -----------------------------------------------------------------------
   # Forge Storage Diff