Fix lints for Rust 1.63 (#3459)

## Issue Addressed

N/A

## Proposed Changes

Fix clippy lints for latest rust version 1.63. I have allowed the [derive_partial_eq_without_eq](https://rust-lang.github.io/rust-clippy/master/index.html#derive_partial_eq_without_eq) lint as satisfying this lint would result in more code that we might not want and I feel it's not required. 

Happy to fix this lint across lighthouse if required though.

common/deposit_contract/build.rs

@@ -54,12 +54,10 @@ fn read_contract_file_from_url(url: Url) -> Result<Value, String> {
                     .map_err(|e| format!("Respsonse is not a valid json {:?}", e))?;
                 Ok(contract)
             }
-            Err(e) => {
-                return Err(format!(
-                    "No abi file found. Failed to download from github: {:?}",
-                    e
-                ))
-            }
+            Err(e) => Err(format!(
+                "No abi file found. Failed to download from github: {:?}",
+                e
+            )),
         }
     }
 }

common/sensitive_url/src/lib.rs

@@ -46,7 +46,7 @@ impl Serialize for SensitiveUrl {
     where
         S: Serializer,
     {
-        serializer.serialize_str(&self.full.to_string())
+        serializer.serialize_str(self.full.as_ref())
     }
 }