[HW candidate] Split websocket_actions.jsx into 2 files for better testing + maintainability

Description

As per the discussion https://github.com/mattermost/mattermost-webapp/pull/3478#discussion_r315266382, refactor websocket handlers into it's own folder/file structure for better maintainability and testing.

From
> Yeah, that'd be a good idea as its own ticket. I'd even say that we could move it into its own folder, so we could have something like actions/websocket/index.js and actions/websocket/handlers.js

QA Test Steps

None

Status

Mana

2

Assignee

Unassigned

Reporter

Ali Farooq

Epic Link

None

Fix versions

Mattermost Team

Apps

Sprint

None

GitHub Issue

None