Remove extra space in metrics fixture

Author: Kyle-Neale

teleport/tests/fixtures/metrics.txt

@@ -775,7 +775,7 @@ teleport_cache_events{cache_component="auth"} 21
 teleport_cache_events{cache_component="node"} 11
 teleport_cache_events{cache_component="proxy"} 20
 # HELP teleport_cache_stale_events Number of stale events received by a Teleport service cache. A high percentage of stale events can indicate a degraded backend.
-# TYPE teleport_cache_stale_events  counter
+# TYPE teleport_cache_stale_events counter
 teleport_cache_stale_events {cache_component="auth"} 1
 teleport_cache_stale_events {cache_component="node"} 2
 teleport_cache_stale_events {cache_component="proxy"} 3