SecretStore: tx retry pattern (#7323)

* SecretStore: auto migrate initial commit

* SecretStore: flush automigrate

* SecretStore: debug flush

* SecretStore: added migration to KeyServerSet contract

* SecretStore: flush automigrate

* SecretStore: flush before testing

* SecretStore: flush

* SecretStore: flush

* SecretStore: bunch of tests for simple ConnectionTrigger && KeyServerSet

* SecretStore: started work on TriggerWithMigration tests

* SecretStore: maintain_session tests

* SecretStore: updated some comments

* SecretStore pass migration_id to ServerSetChangeSession

* SecretStore: fixed lock scope

* SecretStore: fixed error response condition

* SecretStore: fixed ServerSetChange session auto-creation

* SecretStore: update active migration in connector

* removed commented code

* SecretStore: fixed tests compilation

* SecretStore: marked test-related unimplemented-s

* SecretStore: labeled all SS TODOs

* SecretStore: do not read auto-migration stuff when auto-migration is disabled + stripped KeyServerSet contract ABI

* SecretStore: ignore duplicated addresses in KeyServerSet

* fied compilation

* SecretStore: wait for N block confirmations before starting auto-migration

* SecretStore: more tests for migration delay

* SecretStore: clear current nodes set when KSS contract is uninstalled

* SecretStore: retry transaction interval