chore(all): replace map key deletion loop with clear() (#21082)

internal/grid/types.go

@@ -132,9 +132,7 @@ func (m *MSS) Msgsize() int {
 // NewMSS returns a new MSS.
 func NewMSS() *MSS {
 	m := MSS(mssPool.Get())
-	for k := range m {
-		delete(m, k)
-	}
+	clear(m)
 	return &m
 }
 

internal/s3select/csv/record.go

@@ -87,9 +87,7 @@ func (r *Record) Reset() {
 	if len(r.csvRecord) > 0 {
 		r.csvRecord = r.csvRecord[:0]
 	}
-	for k := range r.nameIndexMap {
-		delete(r.nameIndexMap, k)
-	}
+	clear(r.nameIndexMap)
 }
 
 // Clone the record.