Add link to registration form to the unverified user welcome message

[gitjul]

Motivation

An unverified user saw a message encouraging them to register, but without an explanation how to do that right now. That user experience needed to be fixed.

Description

This PR adds a link to the Unbounce form, which is still the way to register, to the welcome message for unverified physicians.

Fixes #316

Implementation

• a link was added to the Message component using the Trans component from i18next
• the PhysicianView was refactored to a function-based React component - this made it possible to pass the eslint pre-commit check by disabling the anchor-has-content rule, but is a good more modern practice anyway
• another rule, no-shadow had to be bypassed because the destructured functions, which needed to be passed to useEffect in props were shadowing the imported actions, and having them left undestructured resulted in a loop, because then the functions were called whenever any of the props changed

Also:

• language names were prepended to translations of PhysicianView that are yet to be added
• two no-unused-vars warnings were removed

Type of change

New feature

Screenshots/Links

[gitjul]

cc @mrememisaac

[gitjul]

@aviskarkc10 I applied changes, ready to re-review