demo-orgs: Hide change password field if email not configured.

Because demo organization owners do not initially have an email
set, some of the personal and organization settings in the web-app
UI should be disabled/hidden until the owner configures an email
address for their account.

Updates showing the password change field in the account & privacy
tab of the personal settings overlay to check if the user's email
being configured (to cover the demo organization case) and if the
organization has enabled password authorization.

web/src/settings.js

@@ -73,6 +73,13 @@ function get_parsed_date_of_joining() {
     );
 }
 
+function user_can_change_password() {
+    if (settings_data.user_email_not_configured()) {
+        return false;
+    }
+    return page_params.realm_email_auth_enabled;
+}
+
 export function build_page() {
     setup_settings_label();
 
@@ -119,6 +126,7 @@ export function build_page() {
         user_is_only_organization_owner: people.is_current_user_only_owner(),
         email_address_visibility_values: settings_config.email_address_visibility_values,
         owner_is_only_user_in_organization: people.get_active_human_count() === 1,
+        user_can_change_password: user_can_change_password(),
     });
 
     settings_bots.update_bot_settings_tip($("#personal-bot-settings-tip"), false);

web/templates/settings/account_settings.hbs

@@ -25,7 +25,7 @@
                 {{/if}}
 
                 <form class="password-change-form grid">
-                    {{#if page_params.realm_email_auth_enabled}}
+                    {{#if user_can_change_password}}
                     <div>
                         <label class="inline-block title">{{t "Password" }}</label>
                         <div class="input-group inline-block" id="pw_change_link">