Fix some typos found by codespell

See,
$ codespell -S "./.git*,./vendor*,./public*"

pkg/services/alerting/extractor.go

@@ -82,12 +82,13 @@ func (e *DashAlertExtractor) getAlertFromPanels(jsonWithPanels *simplejson.Json,
 		if collapsed && collapsedJSON.MustBool() {
 
 			// extract alerts from sub panels for collapsed panels
-			als, err := e.getAlertFromPanels(panel, validateAlertFunc)
+			alertSlice, err := e.getAlertFromPanels(panel,
+				validateAlertFunc)
 			if err != nil {
 				return nil, err
 			}
 
-			alerts = append(alerts, als...)
+			alerts = append(alerts, alertSlice...)
 			continue
 		}
 

pkg/services/alerting/notifiers/teams.go

@@ -74,7 +74,7 @@ func (this *TeamsNotifier) Notify(evalContext *alerting.EvalContext) error {
 	}
 
 	message := ""
-	if evalContext.Rule.State != m.AlertStateOK { //dont add message when going back to alert state ok.
+	if evalContext.Rule.State != m.AlertStateOK { //don't add message when going back to alert state ok.
 		message = evalContext.Rule.Message
 	}