OAK-6756: Convert oak-auth-external to OSGi R7 annotations

[mbaedke]

done.

[jsedding]

With the last commit, the diff in OSGi metadata is as follows

org.apache.jackrabbit.oak.spi.security.authentication.external.impl.DefaultSyncHandler
    MetaType
        Attributes
            - namespace = http://www.osgi.org/xmlns/metatype/v1.0.0 (String)
            + namespace = http://www.osgi.org/xmlns/metatype/v1.2.0 (String)
        Designates
            org.apache.jackrabbit.oak.spi.security.authentication.external.impl.DefaultSyncHandler
                - pid = org.apache.jackrabbit.oak.spi.security.authentication.external.impl.DefaultSyncHandler (String)
        ObjectClassDefinitions
            org.apache.jackrabbit.oak.spi.security.authentication.external.impl.DefaultSyncHandler
                - description = Description for org.apache.jackrabbit.oak.spi.security.authentication.external.impl.DefaultSyncHandler (String)
                + description =  (String)

org.apache.jackrabbit.oak.spi.security.authentication.external.impl.ExternalLoginModuleFactory
    Declarative Services
        References
            syncManager
                - bind = bindSyncManager (String)
                - unbind = unbindSyncManager (String)
                + field-collection = service (String)
            idpManager
                - bind = bindIdpManager (String)
                - unbind = unbindIdpManager (String)
                + field-collection = service (String)
    MetaType
        Attributes
            - namespace = http://www.osgi.org/xmlns/metatype/v1.0.0 (String)
            + namespace = http://www.osgi.org/xmlns/metatype/v1.2.0 (String)
        Designates
            org.apache.jackrabbit.oak.spi.security.authentication.external.impl.ExternalLoginModuleFactory
                - pid = org.apache.jackrabbit.oak.spi.security.authentication.external.impl.ExternalLoginModuleFactory (String)
        ObjectClassDefinitions
            org.apache.jackrabbit.oak.spi.security.authentication.external.impl.ExternalLoginModuleFactory
                - description = Description for org.apache.jackrabbit.oak.spi.security.authentication.external.impl.ExternalLoginModuleFactory (String)
                + description =  (String)

org.apache.jackrabbit.oak.spi.security.authentication.external.impl.principal.ExternalPrincipalConfiguration
    MetaType
        Attributes
            - namespace = http://www.osgi.org/xmlns/metatype/v1.0.0 (String)
            + namespace = http://www.osgi.org/xmlns/metatype/v1.2.0 (String)
        ObjectClassDefinitions
            org.apache.jackrabbit.oak.spi.security.authentication.external.impl.principal.ExternalPrincipalConfiguration
                - description = Description for org.apache.jackrabbit.oak.spi.security.authentication.external.impl.principal.ExternalPrincipalConfiguration
(String)
                + description =  (String)