Fix spelling errors in comments and documentation (#7492)

plugins/processors/topk/README.md

@@ -53,7 +53,7 @@ Note that depending on the amount of metrics on each computed bucket, more than
   # add_rank_fields = []
 
   ## These settings provide a way to know what values the plugin is generating
-  ## when aggregating metrics. The 'add_agregate_field' setting allows to
+  ## when aggregating metrics. The 'add_aggregate_field' setting allows to
   ## specify for which fields the final aggregation value is required. If the
   ## list is non empty, then a field will be added to each every metric for
   ## each field present in this setting. This field will contain

plugins/processors/topk/topk.go

@@ -90,7 +90,7 @@ var sampleConfig = `
   # add_rank_fields = []
 
   ## These settings provide a way to know what values the plugin is generating
-  ## when aggregating metrics. The 'add_agregate_field' setting allows to
+  ## when aggregating metrics. The 'add_aggregate_field' setting allows to
   ## specify for which fields the final aggregation value is required. If the
   ## list is non empty, then a field will be added to each every metric for
   ## each field present in this setting. This field will contain

plugins/processors/topk/topk_test.go

@@ -35,7 +35,7 @@ type metricChange struct {
 	newTags   []tag   // Tags that should be added to the metric
 
 	runHash bool // Sometimes the metrics' HashID must be run so reflect.DeepEqual works
-	// This happens because telegraf.Metric mantains an internal cache of
+	// This happens because telegraf.Metric maintains an internal cache of
 	// its hash value that is set when HashID() is called for the first time
 }
 
@@ -149,7 +149,7 @@ func TestTopkAggregatorsSmokeTests(t *testing.T) {
 
 	aggregators := []string{"mean", "sum", "max", "min"}
 
-	//The answer is equal to the original set for these particual scenarios
+	//The answer is equal to the original set for these particular scenarios
 	input := MetricsSet1
 	answer := MetricsSet1