[CF 5661] v3 - Update LDAP Protocol in fe-connect.c to v3

This branch was automatically generated by a robot using patches from an
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https://commitfest.postgresql.org/patch/5661

The branch will be overwritten each time a new patch version is posted to
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Patch(es): https://www.postgresql.org/message-id/CAKK5BkE0wOGWwZpPcVxzN6ozsjpwVRU51svpbbCfEnDZ3Xcq4Q@mail.gmail.com
Author(s): Andrew Jackson

Author: Commitfest Bot

src/interfaces/libpq/fe-connect.c

@@ -5489,6 +5489,7 @@ ldapServiceLookup(const char *purl, PQconninfoOption *options,
 			   *entry;
 	struct berval **values;
 	LDAP_TIMEVAL time = {PGLDAP_TIMEOUT, 0};
+	int	ldapversion = LDAP_VERSION3;
 
 	if ((url = strdup(purl)) == NULL)
 	{
@@ -5620,6 +5621,15 @@ ldapServiceLookup(const char *purl, PQconninfoOption *options,
 		return 3;
 	}
 
+	if ((rc = ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION, &ldapversion)) != LDAP_SUCCESS)
+	{
+		libpq_append_error(errorMessage, "could not set LDAP protocol version: %s",
+						   ldap_err2string(rc));
+		free(url);
+		ldap_unbind(ld);
+		return 3;
+	}
+
 	/*
 	 * Perform an explicit anonymous bind.
 	 *