omniauth: prevent sending a verification email

`omniauth_registrations_controller.rb` fails to create an account when
the provider doesn't include a required field. This results in the form
being re-rendered leading to a second `#create` call and the creation of
a new `request.env`, causing the loss of data populated by OAuth and
triggering an email confirmation.

See: https://github.com/decidim/decidim/blob/release/0.26-stable/decidim-core/app/commands/decidim/create_omniauth_registration.rb#L75

This patch relies on the `params` to get the `verified_email`.

Closes: #147

.github/workflows/docker-image-production.yml

@@ -19,7 +19,7 @@ jobs:
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           image-name: production
-          image-tag: 1.4
+          image-tag: 1.5
           custom-args: --build-arg RAILS_ENV=production --build-arg FORCE_SSL=false --build-arg SECRET_KEY_BASE=${{ secrets.SECRET_KEY_BASE }} --build-arg MAILER_SENDER=${{ secrets.MAILER_SENDER }}
           dockerfile: docker/decidim.Dockerfile
           build-context: .

app/overrides/controllers/decidim/devise/omniauth_registrations_controller_override.rb

@@ -0,0 +1,7 @@
+Decidim::Devise::OmniauthRegistrationsController.class_eval do
+  private
+
+  def verified_email
+    @verified_email ||= oauth_data.dig(:info, :email) || params.dig(:user, :email)
+  end
+end

app/views/decidim/devise/omniauth_registrations/new.html.erb

@@ -0,0 +1,46 @@
+<div class="wrapper">
+<div class="row collapse">
+  <div class="row collapse">
+    <div class="columns large-8 large-centered text-center page-title">
+      <h1><%= t(".sign_up") %></h1>
+      <p>
+        <%= t(".subtitle") %>
+      </p>
+    </div>
+  </div>
+
+  <div class="row">
+    <div class="columns large-6 medium-10 medium-centered">
+      <div class="card">
+        <div class="card__content">
+          <%= decidim_form_for(@form, namespace: "registration", as: resource_name, url: omniauth_registrations_path(resource_name), html: { class: "register-form new_user" }) do |f| %>
+            <%= form_required_explanation %>
+
+            <div class="user-person">
+              <div class="field">
+                <%= f.text_field :name, help_text: t(".username_help") %>
+              </div>
+            </div>
+
+            <div class="user-person">
+              <div class="field">
+                <% @form.nickname = nil %>
+                <%= f.text_field :nickname, help_text: t(".nickname_help", organization: current_organization.name) %>
+              </div>
+            </div>
+
+            <%= f.hidden_field :email %>
+            <%= f.hidden_field :uid %>
+            <%= f.hidden_field :provider %>
+            <%= f.hidden_field :oauth_signature %>
+
+            <div class="actions">
+              <%= f.submit t(".complete_profile"), class: "button expanded" %>
+            </div>
+          <% end %>
+        </div>
+      </div>
+    </div>
+  </div>
+</div>
+</div>