fix v0.19.0 deploy bugs

[pedroferreira1]

Description

1. TypeError: axios.create is not a function

It's still unclear why this stopped working in this release but using import instead of require fixes the bug. 8cabe6f

2. hooks can only be called inside of the body of a function component.

The method useFlag can't be used inside of class component. 34f4e6f

Acceptance Criteria

• Use import instead of require for axios.
• Refactor Navigation component to a function.

Security Checklist

• Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. More dependencies increase the possibility of one of them being hijacked and affecting us.

[tuliomir]

suggestion(non-blocking): I'd suggest making each of the props explicit, to make it clear what must be passed to this component.

Suggested change

	function Navigation(props) {
	function Navigation({ history }) {

In this specific case, making history explicit will allow us easily modify it to use the following syntax as soon as we upgrade react-router-dom to v5.x:

import { useHistory } from "react-router-dom";

function Navigation() {
  const history = useHistory();
  ...
}

[pedroferreira1]

Done 05763f6