This PR do some loading speed optimization for feeds user interface
pages.
- Load action users batchly but not one by one.
- Load action repositories batchly but not one by one.
- Load action's Repo Owners batchly but not one by one.
- Load action's possible issues batchly but not one by one.
- Load action's possible comments batchly but not one by one.
(cherry picked from commit aed3b53abdd02a3ffbf9e8eb90272ff567333073)