Fix inconsistent use of numeric vs text month in date filter

The selection list now uses full-text months consistently across the
filter page

Fixes #15257

core/date_api.php

@@ -251,7 +251,7 @@ function print_date_selection_set( $p_name, $p_format, $p_date = 0, $p_default_d
 		if( strcmp( $t_char, "m" ) == 0 ) {
 			echo "<select ", helper_get_tab_index(), " name=\"" . $p_name . "_month\"$t_disable>";
 			echo $t_blank_line;
-			print_numeric_month_option_list( $t_date[1] );
+			print_month_option_list( $t_date[1] );
 			echo "</select>\n";
 		}
 		if( strcasecmp( $t_char, "D" ) == 0 ) {