[libkwineffects] Use Q_DISABLE_COPY in AnimationEffect
Summary:
AnimationEffect is an identity so delete copy constructor and copy
assignment operator.
Test Plan: Compiles.
Reviewers: KWin, davidedmundson
Reviewed By: KWin, davidedmundson
Subscribers: kwin
Tags: KWin
Differential Revision: https://phabricator.kde.org/D17838