refactor(config): remove etherscan_api_key fallback from get_rpc_url (#12179)

Update lib.rs

Co-authored-by: grandizzy <38490174+grandizzy@users.noreply.github.com>

Author: zeevick10

crates/config/src/lib.rs

@@ -1400,7 +1400,7 @@ impl Config {
     /// # }
     /// ```
     pub fn get_rpc_url(&self) -> Option<Result<Cow<'_, str>, UnresolvedEnvVarError>> {
-        let maybe_alias = self.eth_rpc_url.as_ref().or(self.etherscan_api_key.as_ref())?;
+        let maybe_alias = self.eth_rpc_url.as_deref()?;
         if let Some(alias) = self.get_rpc_url_with_alias(maybe_alias) {
             Some(alias)
         } else {