ci: use pre-built images

Signed-off-by: Tomás Migone <tomas@edgeandnode.com>

Author: tmigone

.github/workflows/e2e.yml

@@ -23,7 +23,8 @@ jobs:
         run: yarn install --non-interactive --frozen-lockfile
       - name: Run e2e tests
         run: |
-          git clone https://github.com/offchainlabs/nitro
+          git clone https://github.com/tmigone/nitro
+          git checkout ci
           pushd nitro
           git submodule update --init --recursive
           ./test-node.bash --init --no-blockscout --detach