Remove ArticleInsertComplete code

[kghbln]

Setup

• MediaWiki version: 1.29+
• PHP version: 7+1+
• Database and version (MySQL etc.):
• SubPageList version: 2.0.0

Issue

The ArticleInsertComplete hook was removed in MediaWiki 1.29.0. The code still has this artifact included.

Not sure if it is a bug.

[pppery]

Also TitleMoveComplete, which was removed in 1.37.