Save and reload system test

[ChasNelson1990]

Describe the test

We need a series of system tests and visual tests, using BrowserStack Automate, Selenium and Percy Snapshot (@joshuajames-smith), for the following:

• [ ] saving annotations (for each toolbox)
• [ ] loading saved annotations (for each toolbox)
• [ ] editing saved annotations (and resaving and loading) (for each toolbox)

*NOTE: I recommend splitting this issue into one for each annotation for easier tracking of progress but will leave this to @philipjackson ***

[joshuajames-smith]

Relates to https://github.com/gliff-ai/dominate/issues/493