Fix spelling errors in comments and documentation (#7492)

plugins/parsers/wavefront/element.go

@@ -37,7 +37,7 @@ type LiteralParser struct {
 func (ep *NameParser) parse(p *PointParser, pt *Point) error {
 	//Valid characters are: a-z, A-Z, 0-9, hyphen ("-"), underscore ("_"), dot (".").
 	// Forward slash ("/") and comma (",") are allowed if metricName is enclosed in double quotes.
-	// Delta (U+2206) is allowed as the first characeter of the
+	// Delta (U+2206) is allowed as the first character of the
 	// metricName
 	name, err := parseLiteral(p)