Fix workflow for local testnets; reset genesis.json after running script

.github/workflows/local-testnet.yml

@@ -26,7 +26,16 @@ jobs:
             repo-token: ${{ secrets.GITHUB_TOKEN }}
       - name: Install ganache
         run: npm install ganache@latest --global
-
+      - name: Install geth
+        run: |
+          sudo add-apt-repository -y ppa:ethereum/ethereum
+          sudo apt-get update
+          sudo apt-get install ethereum
+        if: matrix.os == 'ubuntu-22.04'
+        run: |
+          brew tap ethereum/ethereum
+          brew install ethereum
+        if: matrix.os == 'macos-12'
       - name: Install GNU sed & GNU grep
         run: |
           brew install gnu-sed grep