The check-methodo option `ignore` won't ignore WDIO Elements

[wswebcreation]

Environment (please complete the following information):

• Node.js version: [e.g. 8.9.1]
• NPM version: [e.g. 5.8.0]
• Browser name and version: [e.g. Chrome 68]
• Platform name and version: [e.g. Windows 10]
• WebdriverIO version: [e.g. 5.1.0]
• @wdio/visual-service version: latest

Config of WebdriverIO + @wdio/visual-service
An example of how you configured the @wdio/visual-service

Describe the bug
When you create a test like this for the web

const result = await browser.checkScreen('web-app', {
  ignore: [$('.navbar__brand')],
  hideElements: [$('.hero__title')]
}) as number

then it will not blockout the element. The code to determine the position and size is not implemented. For now only coordinates work

To Reproduce
See above

Expected behavior
A blockout is created and shown on the diff

Log
If applicable, add logs to help explain your problem. If you don't have log, enable 'debug:true' in the config and paste the log here.
Please use proper markdown to style it

Additional context
Add any other context about the problem here.