Make after version5 cookie index dir compatible with before version5. #1031

Job	Run time
PR Validation	10m 51s
PR Validation	0s
Build with windows on JDK 11	6m 57s
Bookie Tests	20m 9s
Backward compatibility tests	5m 16s
Client Tests	42m 5s
Integration Tests	10m 11s
Replication Tests	17m 2s
Compatibility Check Java8	21m 28s
Build with macos on JDK 11	3m 38s
Remaining Tests	22m 49s
Compatibility Check Java11	23m 22s
TLS Tests	13m 50s
Compatibility Check Java17	25m 17s
OWASP Dependency Check	0s
StreamStorage Tests	20m 32s
Shell tests	38s
	4h 4m 5s

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