Update git submodules

* Update org.eclipse.mylyn from branch 'master'
  to 4ab8ef2d554a5c3bd2c28f5e362b115a98b1f300
  - 519262: add composite update site for 3.25
    
    Change-Id: I84835011a458eaa6852f32ef5eff79db5af166d3
    Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=519262
    
1 file changed