synapse: encrypt LDAP password with age

Switching from Ansible Vault to `age`.

This value is encrypted with the following public key:

    age1j63kzwldegazaaj4rm2ydzlm4wlh6z4cgm4s7g6pzysskh04duhslyc5yy

roles/synapse/templates/homeserver.yaml.j2

@@ -80,7 +80,7 @@ password_providers:
 {% if synapse_ldap_bind_dn|d %}
      bind_dn: '{{ synapse_ldap_bind_dn }}'
 {% if synapse_ldap_bind_password|d %}
-     bind_password: '{{ synapse_ldap_bind_password }}'
+     bind_password: '{{ synapse_ldap_bind_password | decrypt }}'
 {% endif %}
 {% endif %}
 {% endif %}