Image Card: Instill stricter typography styles for slotted content

[daneah]

The problem When paired with global styles that affect the typography of things like p elements, the Image Card can have slotted content that doesn't adhere to its internally-defined typography styles.

The solution Provide a consumer-includable SCSS file for Image Card that gives slotted content the appropriate typography.

Alternatives considered This can be done at the consumer, but can be tedious especially if multiple elements need to be overridden. It's also brittle—if we want to change the Image Card typography later, the consumer would need to as well.