fix: move storage directory into DOKKU_LIB_ROOT
fix: move storage directory into DOKKU_LIB_ROOT

Should this path change in the future, the storage plugin will respect the variable value.

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progrium/dokku,dokku/dokku,progrium/dokku,progrium/dokku,progrium/dokku,dokku/dokku,progrium/dokku,alexquick/dokku,alexquick/dokku,claytonbrown/dokku,claytonbrown/dokku,alexquick/dokku,jimjag/dokku,dokku/dokku,progrium/dokku,claytonbrown/dokku,jimjag/dokku,alexquick/dokku,jimjag/dokku,jimjag/dokku,dokku/dokku,jimjag/dokku,dokku/dokku,claytonbrown/dokku,dokku/dokku,alexquick/dokku,jimjag/dokku,alexquick/dokku,jimjag/dokku,claytonbrown/dokku,jimjag/dokku,dokku/dokku,progrium/dokku,claytonbrown/dokku,progrium/dokku,claytonbrown/dokku,alexquick/dokku,alexquick/dokku,dokku/dokku,claytonbrown/dokku