BaseControllerV2 metadata is required for all the properties (#4612)

## Explanation

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The StateMetadata type in BaseControllerV2 was intended to require each
state property to have associated metadata. However, currently it
doesn't require metadata for optional fields. This is problematic
because all top-level state properties are expected to have metadata,
and will throw an error at runtime if it's missing.

We should update the StateMetadata type to require metadata for all
properties, including optional properties.

## References

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* Fixes #12345
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* Fixes #4252 

## Changelog

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### `@metamask/base-controller`

- **FIXED**: Type of `metadata` in constructor params has been wrapped
in `Required` to make sure metadata required for all properties,
including optional properties.

## Checklist

- [ ] I've updated the test suite for new or updated code as appropriate
- [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [ ] I've highlighted breaking changes using the "BREAKING" category
above as appropriate

packages/base-controller/src/BaseControllerV2.ts

@@ -51,7 +51,7 @@ export type StateDeriver<T extends Json> = (value: T) => Json;
 // TODO: Either fix this lint violation or explain why it's necessary to ignore.
 // eslint-disable-next-line @typescript-eslint/naming-convention
 export type StateMetadata<T extends StateConstraint> = {
-  [P in keyof T]: StatePropertyMetadata<T[P]>;
+  [P in keyof T]-?: StatePropertyMetadata<T[P]>;
 };
 
 /**