Support pydantic field's alias

[igoose1]

I suggest to support pydantic.Field.alias field. Currently erdantic ignores it.

That's an example with simple Gift class:

from pydantic import BaseModel, Field

class Gift(BaseModel):
    for_: str = Field(alias="for")

erdantic produces:

Although, pydantic displays a field as for:

>>> Gift.schema()
{'title': 'Gift', 'type': 'object', 'properties': {'for': {'title': 'For', 'type': 'string'}},
'required': ['for']}

Libraries like FastAPI use that schema in Swagger generations.