Use pydantic shims (#85)

Author: joostlek

poetry.lock

@@ -3,7 +3,10 @@
 
 from dataclasses import dataclass
 
-from pydantic import BaseModel, Field
+try:
+    from pydantic.v1 import BaseModel, Field
+except ImportError:  # pragma: no cover
+    from pydantic import BaseModel, Field  # type: ignore[assignment] # pragma: no cover
 
 from .const import AircraftCategory, PositionSource
 from .exceptions import OpenSkyCoordinateError