Free space specification change/page builder update

【Contents of modification】
■Changed specifications so that the style of the article body is applied to the top page free space.
■Updated page builder.
・【Firefox, IE】Fixed the problem that Google map is unstable.
・Fixed the bug of switching editor and adjusted CSS in WordPress 5.5.
・Fixed a bug that the checkbox of the block border was removed when duplicating a block.
・Fixed other minor bugs.

The following are the files that have been modified in this update.

【Modified file】
front-page.php
languages/ja.mo
languages/ja.po
pagebuilder/assets/admin/css/admin.css
pagebuilder/assets/admin/js/admin.js
pagebuilder/modules/googlemap.php
pagebuilder/modules/simple_table.php
pagebuilder/modules/slider.php
pagebuilder/pagebuilder.php
style.css