[BACK] Remove deprecated `User::getUsername`

[homersimpsons]

This method is deprecated, we should remove it entirely

symfony-boilerplate/apps/back/src/Entity/User.php

Lines 57 to 61 in 91be84c

	/** @deprecated since Symfony 5.3, use getUserIdentifier instead */
	public function getUsername(): string
	{
	return $this->email;
	}