Build/Test Tools: Update CSS files after grunt precommit:css.

This removes instances of the `-moz-user-select` property, which was required until Firefox 68.

Firefox is currently in version 84, so these can safely be removed.

Fixes #52332.
Built from https://develop.svn.wordpress.org/trunk@49991


git-svn-id: http://core.svn.wordpress.org/trunk@49692 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/css/editor-rtl.css

@@ -258,7 +258,6 @@ div.mce-inline-toolbar-grp {
 	box-sizing: border-box;
 	margin-bottom: 8px;
 	position: absolute;
-	-moz-user-select: none;
 	-webkit-user-select: none;
 	-ms-user-select: none;
 	user-select: none;

wp-includes/css/editor.css

@@ -257,7 +257,6 @@ div.mce-inline-toolbar-grp {
 	box-sizing: border-box;
 	margin-bottom: 8px;
 	position: absolute;
-	-moz-user-select: none;
 	-webkit-user-select: none;
 	-ms-user-select: none;
 	user-select: none;

wp-includes/css/media-views-rtl.css

@@ -610,7 +610,6 @@
 	border-left-style: solid;
 	border-left-color: #ccc;
 	-webkit-user-select: none;
-	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 }
@@ -950,7 +949,6 @@
 	list-style: none;
 	text-align: center;
 	-webkit-user-select: none;
-	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 	width: 25%;

wp-includes/css/media-views.css

@@ -609,7 +609,6 @@
 	border-right-style: solid;
 	border-right-color: #ccc;
 	-webkit-user-select: none;
-	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 }
@@ -949,7 +948,6 @@
 	list-style: none;
 	text-align: center;
 	-webkit-user-select: none;
-	-moz-user-select: none;
 	-ms-user-select: none;
 	user-select: none;
 	width: 25%;