Provide support for forward-byte-order cert validation for SmartCard Auth

During the investigation for https://gitlab.com/gitlab-com/request-for-help/-/issues/1855 we discovered that customer certs may be in forward byte order than the reverse byte order that GitLab attempts to parse through in https://gitlab.com/gitlab-org/gitlab/-/blame/master/ee/lib/gitlab/auth/smartcard/ldap_certificate.rb?ref_type=heads#L66. A patch provided in the RFH addresses and can be considered to add an optional setting/configuration for users to use the variant format instead