Update CSP (#22)

Author: pablomendezroyo

next.config.mjs

@@ -185,6 +185,11 @@ export default withBundleAnalyzer({
         // Apply these headers to all routes in your application.
         source: '/(.*)',
         headers: [
+          // DAPPNODE
+          {
+            key: "Content-Security-Policy",
+            value: `connect-src 'self' https: wss: http: http://execution.holesky.dncore.dappnode:8545 http://execution.mainnet.dncore.dappnode:8545 http://lido-events.lido-csm-holesky.dappnode:8080 http://lido-events.lido-csm-mainnet.dappnode:8080 http://brain.web3signer-holesky.dappnode http://brain.web3signer.dappnode;`,
+          },
           {
             key: 'X-DNS-Prefetch-Control',
             value: 'on',