Configuring ELECTRIC_STORAGE_DIR is not enough for Electric to use that directory

[alco]

The ELECTRIC_STORAGE_DIR configuration allows one to define the root directory for Electric's disk storage, under which it will create subdirectories for shape logs and the persistent KV store. However, setting this option alone doesn't work as intended: both the shape log store and the persistent KV store use the default ./persistent root directory unless the ELECTRIC_STORAGE=file and ELECTRIC_PERSISTENT_STATE=file configuration options are also set.

I don't think this is the intended behaviour. Both shape store and persistent KV store default to using the disk if not explicitly configured, but they should use the configured ELECTRIC_STORAGE_DIR as the root dir in that case too.