[Security Solution] Actions from investigation guide form builder

[kqualters-elastic]

Part of https://github.com/elastic/security-team/issues/4824

Issue to track adding a form and markdown plugin to render insight markdown snippet upon form submission, form state is serialized into the correct markdown plugin string, the existing markdown parser will render the button correctly.

Form will look the same as the existing query builder form from unified search plugin.

[elasticmachine]

Pinging @elastic/security-solution (Team: SecuritySolution)