Added Serde, Store, PartialEq, Debug and Display for NonZero.

[orizi]

Stack:

• Removed diagnostics not related to test. #4798
• Better mapping of embeddable_as diagnostics. #4797
• Added warnings for bad embeddable impls. #4796
• Added Serde, Store, PartialEq, Debug and Display for NonZero. #4795 ⬅

⚠️ Part of a stack created by spr. Do not merge manually using the UI - doing so may have unexpected results.

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This change is 

[gilbens-starkware]

Reviewed 5 of 6 files at r1, all commit messages.
Reviewable status: 5 of 6 files reviewed, 1 unresolved discussion (waiting on @orizi)

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corelib/src/starknet/storage_access.cairo line 277 at r1 (raw file):

    #[inline]
    fn unpack(value: T) -> NonZero<T> {
        value.try_into().expect('StoreNonZero - non zero value')

Or non NonZero value.

Suggestion:

zero value

[gilbens-starkware]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @orizi)