Change 'My [org]' button to 'Login' (#3369)

Fixes #3366

hypha/public/utils/templates/utils/includes/login_button.html

+{% load i18n %}
 <a href="{{ APPLY_SITE.root_url }}{% url 'users_public:login' %}" class="button button--transparent button--contains-icons {{ class }}">
     <svg class="icon icon--person"><use xlink:href="#person-icon"></use></svg>
+    {% if user.is_authenticated %}
     My {{ ORG_SHORT_NAME }}
+    {% else %}
+    {% trans "Login" %}
+    {% endif %}
 </a>