[FEATURE] New look task_card

[ChrisMarsh82]

What?
Add a variant of the task card to match Facilitator Mexico designs.

Note: must be greyed out once completed.

How?
The number on the left hand side should be an image and not another value to be passed. task_card already supports images so it would just be styling changes needed. This would also give authors more flexibility in the future.

[jfmcquade]

@FaithDaka This should be achievable as a variant of the task-card component. I'm not sure what the best name for the variant would be, maybe something like block-button/button-block?

There's quite a lot of logic in the task card component that you can ignore, the button variant is probably the one to build from as this strips out a lot of the other elements. You can handle the two colour states by reading the existing progressStatus property, and checking whether it is "completed" (this is already added as a class on some of the child elements within the component, for example).