Update slapd.conf so that openldap syncrepl over TLS

This change updated slapd.conf so that openldap syncrepl will
be configured to be secure over TLS.

Test Plan:
PASS: DX system deployment
PASS: Check syncrepl section in slapd.conf.backup, it should contain:
      tls_cert="/etc/ldap/certs/openldap-cert.crt"
      tls_key="/etc/ldap/certs/openldap-cert.key"
      tls_cacert="/etc/ssl/certs/ca-certificates.crt"
      tls_reqsan=demand

Story: 2009834
Task: 46246
Depends-On: https://review.opendev.org/c/starlingx/ansible-playbooks/+/856766
Signed-off-by: Andy Ning <andy.ning@windriver.com>
Change-Id: Ia3bb31a733cb976ea9c5d0428b64f012dc9ec57e

openldap-config/source-debian/slapd.conf

@@ -101,6 +101,10 @@ ppolicy_use_lockout
 # syncrepl directives for each of the other masters
 syncrepl rid=000 
   provider=ldap://controller-1
+  tls_cert="/etc/ldap/certs/openldap-cert.crt"
+  tls_key="/etc/ldap/certs/openldap-cert.key"
+  tls_cacert="/etc/ssl/certs/ca-certificates.crt"
+  tls_reqsan=demand
   type=refreshAndPersist
   retry="5 5 300 +" 
   searchbase="dc=cgcs,dc=local"