goto: don't center the current line when the user specified a column only

This does not quite do what I would have liked (scroll only when needed)
when on a softwrapped line and jumping to a different chunk, but... it's
still better than needlessly centering the line.

(The user can still center the line, if that is what they want, by using
a period or a slash instead of a comma.)

This addresses https://savannah.gnu.org/bugs/?63008.

src/search.c

@@ -829,9 +829,9 @@ void goto_line_and_column(ssize_t line, ssize_t column, bool retain_answer,
 		openfile->placewewant = breadth(openfile->current->data);
 #endif
 
-	/* When the position was manually given, center the target line. */
+	/* When a line number was manually given, center the target line. */
 	if (interactive) {
-		adjust_viewport(CENTERING);
+		adjust_viewport((*answer == ',') ? STATIONARY : CENTERING);
 		refresh_needed = TRUE;
 	} else {
 		int rows_from_tail;