Quay config app set LDAPS with customized certificate was failed to save configurations

Description:
This is an issue found when set LDAPS with Quay Config app, now for the tartget LDAP server it was using self singed cert, it will not be trusted by client side; On Quay config app upload the TLS cert of the LDAP server, the results is that it was failed to save configurations.
refer to the screenshots of the Quay config-app.

Steps:
1. Open Quay config app
2. Go to "Internal Authentication" section, choose LDAP and upload Custom SSL Certificates of LDAP server
3. In the "LDAP URI: ", give "ldaps://quayldap.qe.gcp.devcluster.openshift.com"
4. Give other reuqired configurations inlcuding Base DN, User Relative DN, Administrator DN and Administrator DN password
5. At the section "Custom TLS Certificate", upload the self signed cert of target LDAP server
6. Click "Save Configurations"

Expected Results:
Quay config app can save the configurations successfully.

Acutal Results:
Quay config app can't save configurations.

Quay Config app POD logs:
2020-04-30 09:36:45,752 [41] [DEBUG] [data.users.externalldap] TLS Fallback enabled in LDAP
gunicorn-config stdout | 2020-04-30 09:36:45,752 [41] [DEBUG] [data.users.externalldap] TLS Fallback enabled in LDAP
2020-04-30 09:36:45,890 [41] [ERROR] [util.config.validator] Validation exception
Traceback (most recent call last):
File "/quay-registry/util/config/validator.py", line 87, in validate_service_for_config
VALIDATORS[service](validator_context)
File "/quay-registry/util/config/validators/validate_ldap.py", line 56, in validate
raise ConfigValidationException(values.get("desc", "Unknown error"))
ConfigValidationException: Can't contact LDAP server
gunicorn-config stdout | 2020-04-30 09:36:45,890 [41] [ERROR] [util.config.validator] Validation exception
Traceback (most recent call last):
File "/quay-registry/util/config/validator.py", line 87, in validate_service_for_config
VALIDATORS[service](validator_context)
File "/quay-registry/util/config/validators/validate_ldap.py", line 56, in validate
raise ConfigValidationException(values.get("desc", "Unknown error"))
ConfigValidationException: Can't contact LDAP server