3.0.0-beta3

refactor(SessionHandler): SessionAdministrator decorates SessionHandler instead of holding components
feat(SessionHandler): add SessionAdministrator for cross-session ops
refactor(SessionHandler): deprecate legacy Storage_Hashtable and HashtableBackend in favor of ModernHashtableBackend
feat(SessionHandler): add ModernHashtableBackend using Horde\HashTable\LockableHashTable
style: php-cs-fixer
chore: Update workflow dependency