Fix renaming directory symlinks on Linux.

drivers/unix/dir_access_unix.cpp

@@ -397,12 +397,18 @@ Error DirAccessUnix::rename(String p_path, String p_new_path) {
 	}
 
 	p_path = fix_path(p_path);
+	if (p_path.ends_with("/")) {
+		p_path = p_path.left(-1);
+	}
 
 	if (p_new_path.is_relative_path()) {
 		p_new_path = get_current_dir().path_join(p_new_path);
 	}
 
 	p_new_path = fix_path(p_new_path);
+	if (p_new_path.ends_with("/")) {
+		p_new_path = p_new_path.left(-1);
+	}
 
 	return ::rename(p_path.utf8().get_data(), p_new_path.utf8().get_data()) == 0 ? OK : FAILED;
 }