*add From<Result<String, ()>> for ClientError

ethers-providers/src/transports/http.rs

@@ -75,6 +75,23 @@ impl From<wasm_bindgen::JsValue> for JsonRpcError {
     }
 }
 
+impl From<Result<String, ()>> for ClientError {
+    fn from(result: Result<String, ()>) -> Self {
+        match result {
+            Ok(msg) => ClientError::JsonRpcError(JsonRpcError {
+                code: 0,
+                message: msg,
+                data: None,
+            }),
+            Err(_) => ClientError::JsonRpcError(JsonRpcError {
+                code: 0,
+                message: "response is not a string".to_string(),
+                data: None,
+            }),
+        }
+    }
+}
+
 #[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
 #[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl JsonRpcClient for Provider {