feat: password reset (#179) (#186)

* feat: password reset via symfonycasts/reset-password-bundle (#179)

Implements the full password reset flow using the SymfonyCasts reset-password-bundle.

* ci: share base layer cache between dev and prod builds

* fix: use CSS form selector in tests instead of translated button text

* fix: translate missing validator string for reset password email field

* fix: translate reset password form labels via TranslatorInterface

* ci: override MAILER_DSN to null for PHPUnit so mailer host is not required

templates/backoffice/registration/register.html.twig

@@ -2,7 +2,7 @@
 {% block title %}{{ 'Register'|trans }}{% endblock %}
 
 {% block body %}
-    <h3>{{ 'Register'|trans }}</h3>
+    <h3 class="mb-3">{{ 'Register'|trans }}</h3>
 
     {{ form_errors(registrationForm) }}