wrap flashbots url in option

Author: dylanlott

src/config.rs

@@ -95,7 +95,7 @@ pub struct BuilderConfig {
         desc = "Flashbots endpoint for privately submitting rollup blocks",
         optional
     )]
-    pub flashbots_endpoint: url::Url,
+    pub flashbots_endpoint: Option<url::Url>,
 
     /// Address of the Zenith contract on Host.
     #[from_env(var = "ZENITH_ADDRESS", desc = "address of the Zenith contract on Host")]

src/test_utils.rs

@@ -32,7 +32,7 @@ pub fn setup_test_config() -> Result<BuilderConfig> {
             .try_into()
             .unwrap(),
         tx_broadcast_urls: vec!["http://localhost:9000".into()],
-        flashbots_endpoint: "http://localhost:9062".parse().unwrap(), // NB: Flashbots API default
+        flashbots_endpoint: Some("http://localhost:9062".parse().unwrap()), // NB: Flashbots API default
         zenith_address: Address::default(),
         quincey_url: "http://localhost:8080".into(),
         builder_port: 8080,