Update headers handling for http source

internal/http/http.go

@@ -37,7 +37,7 @@ func handleHTTP(rawURL string) (core.Producer, error) {
 		query := streams.ParseQuery(rawQuery)
 		for _, header := range query["header"] {
 			key, value, _ := strings.Cut(header, ":")
-			req.Header.Add(key, value)
+			req.Header.Add(key, strings.TrimSpace(value))
 		}
 	}