* [MM-18766] removed deprecated lifecycle methods from post components
* [MM-18766] update snapshot, seems like there was a bug
* [MM-18766] refactor getBestImageUrl -> getBestImageUrlAndDimensions
- refactor getBestImageUrl to take a single argument: props
- refactor getViewPostWidth to take a single argument: props
* [MM-18766] getDerivedStateFromProps was previously returning only first prop change
- fix issue if multiple props were modified at once.
* [MM-18766] removed FastImage.preload that was supposed to be removed in the last merge.
* [MM-18766] removed getDerivedStateFromProps
* [MM-18766] fix tests based on actual component being completely re-rendered rather than prop change.
* [MM-18766] cleaning up initial changes due to no longer using getDerivedStateFromProps method
- move back getBestImageUrl and getViewPostWidth from outside of components
- keep the renaming of getBestImageUrl
- remove the use of spread operator as it is also no longer needed
* [MM-18766] one of caller to getViewPostWidth is still passing this.props
- this is no longer needed
* Enable ESLint no-unused-vars
* Use FastImage instead of Image
* Update fast-image patch to support multiple cookies
* Fix ESLint errors
* Have jest run timers for post_textbox tests
* Feedback review
* Update snapshots
* update eslint's `comma-dangle` rule to `always-multiline`
* add check and fix scripts to package.json
* Invoke `yarn fix` to adopt the updated eslint rules. No other changes are included.
