Remove asynchronous code from Page Editor reducers

• Type: Task
• Status: Closed
• Priority: Minor
• Resolution: Discarded
• Affects Version/s: None
• Fix Version/s: None
• Component/s: Pages > Page Editor
• Labels: None

We use reducers (https://redux.js.org/basics/reducers) to manage our application status, and although we adopted an async-reducer pattern, we've seen that this is a quite limited approach at the end, as we are not able to control when/how actions are completed.

Step by step, we are moving to the action-thunk pattern (https://github.com/reduxjs/redux-thunk#motivation), which looks much more scalable.

These are the reducers we need to migrate:

[ ] addFragmentEntryLinkReducer
[ ] getFragmentEntryLinkContent
[ ] moveFragmentEntryLinkReducer
[ ] updateFragmentEntryLinkReducer
[ ] updateFragmentEntryLinkConfigReducer
[x] addPortletReducer
[ ] addRowReducer
[ ] moveRowReducer
[x] updateRowConfigReducer
[ ] createSegmentsExperienceReducer
[ ] deleteSegmentsExperienceReducer
[ ] selectSegmentsExperienceReducer
[ ] editSegmentsExperienceReducer
[ ] updateSegmentsExperiencePriorityReducer

/cc Victor Galan Sandro Chinea