app/views/user_mailer/reset_password_instructions.text.erb
<%= t 'devise.mailer.reset_password_instructions.title' %>
===
<%= t 'devise.mailer.reset_password_instructions.explanation' %>
=> <%= edit_password_url(@resource, reset_password_token: @token) %>
<%= t 'devise.mailer.reset_password_instructions.extra' %>