[Feature] Introduce storage_alias for CountedStorageMap (#13366)

* [Feature] Introduce storagage_alias for CountedStorageMap

* bit more dry

* bit more dry

* address review comments

* some tests and fixes

* fix ui tests

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <[email protected]>

* compare metadata

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Co-authored-by: parity-processbot <>
Co-authored-by: Bastian Köcher <[email protected]>