Update Substrate (#808)

* Update to latest Substrate master

* upgrade decl_storage declaration

* Companion PR to Substrate#4752

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: thiolliere <gui.thiolliere@gmail.com>
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
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