Prep for release (2.4.59)

CHANGES

 OpenLDAP 2.4 Change Log
 
-OpenLDAP 2.4.59 Engineering
+OpenLDAP 2.4.59 Release (2021/06/03)
 	Fixed libldap TLSv1.3 cipher suites with OpenSSL 1.1.1 (ITS#9521)
 	Fixed libldap double free of LDAP_OPT_DEFBASE (ITS#9530)
 	Fixed slapd syncrepl handling of add+delete on single value attr (ITS#9295)

build/version.var

@@ -15,9 +15,9 @@
 ol_package=OpenLDAP
 ol_major=2
 ol_minor=4
-ol_patch=X
-ol_api_inc=20458
+ol_patch=59
+ol_api_inc=20459
 ol_api_current=13
-ol_api_revision=6
+ol_api_revision=7
 ol_api_age=11
-ol_release_date="2021/03/16"
+ol_release_date="2021/06/03"