add missing props to ic-search-bar

[j212122]

Summary

ic-search-bar does not currently support the following props which are attributes of its native counterpart.

form minlength

This ticket is to add them to the component

💰 Use value

Adding these props will increase functionality and give developers more options when implementing the component

Additional info

https://www.w3schools.com/tags/tag_input.asp

[ASM995]

Need to investigate if these are actually required.

[GCHQ-Developer-299]

I created a branch for this, but the more I think about it, I don't think we need form and minlength:

• 'form': this is required when you have an element that is physically outside a
  but needs to be included in it, but the search bar component has its own internal submit logic and isn't normally going to be inside forms - and if it were inside one, it's got logic to get the nearest form element (see handleSubmitSearch())

  • We advise against using the search bar inside forms: "Don't use a search bar with search results if you are likely to need additional filters and advanced search settings. It's better to use a search bar with a custom search results page in this case."
  • 'minlength': this is most commonly used for password entry elements. And we already have the charactersUntilSuggestion prop for preventing search until a certain number of characters are entered.