Remove unused code and broken tests and fixes

[shjortConcordium]

Purpose

Cleanup repository

Changes

• Removed unused code from deserializationHelpers
• Removed deserializeSchema / getContractSchema (Not exported from index and unused)
• Removed tests for removed code.
• Removed broken tests related to old testnet / GRPC v1 client.
• Removed disabling wasm-opt on release builds. (It was added due to a bug, I believe this is the relevant issue wasm-opt: Exported global cannot be mutable rustwasm/wasm-pack#886)
• Fix broken serialization in get_credential_deployment_details_aux.
• Added build:dev option to quickly build without wasm-opt / regenerating the grpc api.

Checklist

• My code follows the style of this project.
• The code compiles without warnings.
• I have performed a self-review of the changes.
• I have documented my code, in particular the intent of the
  hard-to-understand areas.
• (If necessary) I have updated the CHANGELOG.

[rasmus-kirk]

LGTM