fix clippy

Author: the2pizza

performance_measurement/src/profiler.rs

@@ -36,7 +36,7 @@ pub struct PerformanceProfiler;
 
 impl PerformanceProfiler {
     pub fn store_measurement(function_name: &'static str, duration: Duration) {
-        let mut global_performance_measurements = &GLOBAL_PERFORMANCE_MEASUREMENTS;
+        let global_performance_measurements = &GLOBAL_PERFORMANCE_MEASUREMENTS;
 
         let duration_ms = duration.as_nanos() as f64 / 1_000_000.0;