Resolving FIPS incompliance in gardener/landscaper: Usage of sha1.New() in secretName

https://github.com/gardener/landscaper/blob/c838a679a4b07140ac8eb691180ac8dea907c692/pkg/landscaper/installations/executions/template/state.go#L95

=> here we definitely need to write some migration code. The sha is basically being used to generate an object name to store and retrieve data. So we definitely would need to migrate old hashes to new ones