[Form components] Change size prop default value to fillParent

[GomezIvann]

After seeing other design systems I think fillParent suits better our form components, since we now can know in which containers they will be fitted (Layout components) and predict that "medium" is the most used size, in my opinion, is a bit pretentious. This change would affect:

1. Text input, Number input, Password input, Date input and Textarea.
2. Select.
3. ...?

Approaches:

• Kaizen: https://cultureamp.design/components/text-field/
• Braid: https://seek-oss.github.io/braid-design-system/components/TextField
• Shopify: https://polaris.shopify.com/components/forms/form#navigation
• Ant: https://ant.design/components/input/
• Atlassian: https://atlassian.design/components/textfield/examples

[marcialfps]

I fully agree. If we provide layout components we should at least delete fixed sizes.

Also, I think Alex had the idea of deleting the size prop from all components, so the best idea is to continue with that goal.