Various minor fixes (#13945)

* Fix: Incorrect implementation of can_reserve check

* Fix: Incorrect migration of consumer counting for existing accounts with frozen amounts

* Fix: Inconsistent implementation between assets can_deposit and new_account

* Fixes

* Fixes

* Another fix

* Update tests.rs

* Update fungible_tests.rs

* Use `can_accrue_consumers` in the body of `can_inc_consumer`

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Co-authored-by: Keith Yeung <[email protected]>
Co-authored-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: parity-processbot <>