Fix spacing

Author: utpilla

opentelemetry-prometheus/tests/integration_test.rs

@@ -822,7 +822,7 @@ fn gather_and_compare_multi(
     let metric_families = registry.gather();
     encoder.encode(&metric_families, &mut output).unwrap();
 
-    let output_string = if cfg!(windows){
+    let output_string = if cfg!(windows) {
         String::from_utf8(output).unwrap().replace('\n', "\r\n")
     } else {
         String::from_utf8(output).unwrap()