feat: Unmarshal Nonce type

[leovct]

Description

When trying to unmarshal types.Block, there is an issue with types.Nonce. The type is missing its custom UnmarshalText method.

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Breaking changes

Please complete this section if any breaking changes have been made, otherwise delete it

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

Manual tests

Please complete this section if you ran manual tests for this functionality, otherwise delete it

Documentation update

Please link the documentation update PR in this section if it's present, otherwise delete it

Here's an example of a CI job deserialising a block: https://github.com/leovct/edge-grpc-mock-server/actions/runs/6025058222/job/16345020813#step:6:38

Additional comments

Please post additional comments in this section if you have them, otherwise delete it

[github-actions]

CLA Assistant Lite bot All contributors have signed the CLA ✍️ ✅

[leovct]

I have read the CLA Document and I hereby sign the CLA

[vcastellm]

LGTM