Resend confirmation instructions

<%= form_for :user, ~p"/confirmations", fn f -> %>
<%= email_input(f, :email, placeholder: "Email", class: "input", required: true) %>
<%= render(PhilomenaWeb.CaptchaView, "_captcha.html", name: "confirmation", conn: @conn) %>
<%= submit("Resend confirmation instructions", class: "button") %>
<% end %>