Tweak telemetry manager test to not be flaky

Summary:
The `test_lifecycle` test is intended to confirm that we do get multiple segments.

On a lightly loaded machine, the timing should be zero. This is not always the case, so to avoid flakiness we manually zero out the timing, so the essence of the test is not flaky

Reviewed By: jcpetruzza

Differential Revision: D85661410

fbshipit-source-id: b7d1130929692360a1284c78787f89f4e537cd88

Author: alanz

crates/elp/src/server/telemetry_manager.rs

@@ -278,12 +278,14 @@ mod test {
             // Control lock scope by having it in braces
             let mut telemetry = TEST_TELEMETRY.lock();
             telemetry.next_segment(token.clone(), None);
-            let new = telemetry.active.get(&token).unwrap();
+            let new = telemetry.active.get_mut(&token).unwrap();
             assert_ne!(orig.segment_start_time, new.segment_start_time);
             assert_eq!(orig.start_time, new.start_time);
+            // We sometimes run on a rollover boundary, set the value to zero to avoid flakiness
+            for seg in &mut new.segments {
+                seg.1 = 0;
+            }
             let expected = format!("{:#?}\n", &new.segments);
-            // We sometimes run on a rollover boundary
-            let expected = expected.replace("1", "0");
             expect![[r#"
                 [
                     (