Removed test email function from Labs

no refs.
- removes leftover test email section from Labs to resolve a lot of confusion around it

ghost/admin/app/controllers/settings/labs.js

@@ -217,19 +217,6 @@ export default Controller.extend({
         return RSVP.resolve();
     },
 
-    sendTestEmail: task(function* () {
-        let notifications = this.notifications;
-        let emailUrl = this.get('ghostPaths.url').api('mail', 'test');
-
-        try {
-            yield this.ajax.post(emailUrl);
-            notifications.showAlert('Check your email for the test message.', {type: 'info', key: 'test-email.send.success'});
-            return true;
-        } catch (error) {
-            notifications.showAPIError(error, {key: 'test-email:send'});
-        }
-    }).drop(),
-
     saveSettings: task(function* () {
         return yield this.settings.save();
     }).drop(),

ghost/admin/app/templates/settings/labs.hbs

@@ -213,19 +213,6 @@
             </div>
         </div>
 
-        <div class="gh-setting-header">Testing tools</div>
-        <div class="flex flex-column br3 shadow-1 bg-grouped-table pa5 mt2">
-            <div class="gh-setting-first gh-setting-last">
-                <div class="gh-setting-content">
-                    <div class="gh-setting-title">Test email configuration</div>
-                    <div class="gh-setting-desc">Send yourself a test email to make sure everything is working</div>
-                </div>
-                <div class="gh-setting-action">
-                    <GhTaskButton @buttonText="Send" @successText="Sent" @task={{this.sendTestEmail}} @class="gh-btn gh-btn-hover-blue gh-btn-icon" />
-                </div>
-            </div>
-        </div>
-
     </section>
 </section>