RB-2548: Add max element amount to MdAutocomplete

[turiddahl]

Describe your changes

Adds the variable amountOfElementsShown to the MdAutocomplete component. It makes it possible to set a maximum amount of elements shown in the dropdown, which is useful when you have a very long list of options.

It has a default value of null, that returns the whole list. So it does not change existing instances of this component.

Checklist before requesting a review

• [X] I have performed a self-review and test of my code
• [X] I have added label to the PR (major, minor or patch)
• [ ] If new component: Is story for component created in stories-folder?
• [ ] If new component: Is tsx-file import added to packages/react/index.tsx?
• [ ] If new component: Is css-file added to packages/css/index.css?

[github-actions[bot]]

Please set a versioning label of either major, minor, or patch to the pull request.

[aurorascharff]

Vi har allerede en property dropdownHeight. Hva tenker du om den propertien mot denne nye? Det er kanskje lettere å bruke et antall options?

[turiddahl]

@aurorascharff ja jeg så den, men jeg vil ikke kun minke størrelsen på dropdownen. Det er såppas store lister at scrollbaren blir veldig liten og veldig vanskelig å bruke om vi kun bruker dropdownHeight.

[aurorascharff]

Jeg skjønner! Flott :)