docs: corrected grammatical error in Keptn Metrics (keptn#3210)

Signed-off-by: AryanBakliwal <[email protected]>

docs/docs/getting-started/metrics.md

@@ -29,8 +29,7 @@ Each has plugins but it is difficult to maintain them,
 especially if you are using multiple tools,
 and multiple observability platforms,
 and multiple instances of some tools or observability platforms.
-The Keptn metrics feature unites all these metrics
-integrates metrics from all these sources into a single set of metrics.
+The Keptn metrics feature unites metrics from all these sources into a single set.
 
 ## Using this exercise