Fix a crash when fetching annual data without a previous year

[JeremieCharest]

This PR fix a NPE when fetching annual data on a contract without previous year data (new contract or a move). It also fix a NPE when the CLI failed to authenticate and try to clean a non-existent session.

Steps to reproduce :

• With a contract without previous data, invoke the cli with the following options :
  • -u xxx-user--xxx -p xxx-password-xxx -c xxx-14123-xxx -L INFO
  • it could also be reproduce with the -H option
• Last logged line should contain Fetching annual data
• An out of context 'compare' message should be printed

Expected behavior : The CLI should not crash and report the current year data

[titilambert]

Thanks !