Addressed clippy warnings

Author: UebelAndre

test/cargo_build_script/tools_exec.rs

@@ -3,7 +3,6 @@ pub fn test_tool_exec() {
     let tool_path = env!("TOOL_PATH");
     assert!(
         tool_path.contains("-exec-"),
-        "tool_path did not contain '-exec-': {}",
-        tool_path
+        "tool_path did not contain '-exec-'",
     );
 }

test/process_wrapper/rustc_quit_on_rmeta.rs

@@ -68,8 +68,7 @@ mod test {
         ]);
         assert!(
             !out_content.contains("should not be in output"),
-            "output should not contain 'should not be in output' but did: {}",
-            out_content
+            "output should not contain 'should not be in output' but did",
         );
     }