[Bulma Cleanup] Remove Bulma dependency from Caption and Heading components

[helloanil]

Context/background

We want our Design System (atomic components in the shared-atomic-design-components folder) to be completely independent of React Bulma Components.

What needs to be done?

• Heading dependency imported from react-bulma-components needs to be removed in Caption
• Heading dependency imported from react-bulma-components needs to be removed in Heading
• The same design should be achieved by using semantic HTML heading