Adds an optional `supported_schemas` feature to the fields.

One can decide to limit the support for a particular field to:
- A schema designated by name,
- A schema, until a specific version,
- A schema, from a specific version.

When the GraphQL schema is being built, we may pass an identifier for the current
schema name and version and the fields will be filtered appropriately.

Examples of field definitions:

```python
@strawberry.type
class User:
    # [...]

    @strawberry.field(name="debugMessage", supported_schemas=[
        SupportedSchema(name="internal"),
    ])
    def get_debug_message(self) -> str:
        # This field will only appear in the schemas called `internal`
        # [...]

    @strawberry.field(name="riskScore", supported_schemas=[
        SupportedSchema(name="internal", until_version="1.2"),
    ])
    def get_old_risk_score(self) -> float:
        # This field will only appear in the schemas called `internal` that have
        # a version lower than or equal to `1.2`
        # [...]

    @strawberry.field(name="riskScore", supported_schemas=[
        SupportedSchema(name="internal", from_version="1.3"),
    ])
    def get_new_risk_score(self) -> float:
        # This field will only appear in the schemas called `internal` that have
        # a version higher than or equal to `1.3`
        # [...]
```

Examples of schema definition:

```python
internal_schema = strawberry.Schema(
    query=Query,
    mutation=Mutation,
    schema_identifier=SchemaIdentifier(name="internal", version="1.4"),
)
```

for more information, see https://pre-commit.ci