Use shorter notation to import Sample

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

src/frequenz/sdk/timeseries/_ringbuffer.py

@@ -14,7 +14,7 @@
 import numpy as np
 import numpy.typing as npt
 
-from frequenz.sdk.timeseries import Sample
+from . import Sample
 
 FloatArray = TypeVar("FloatArray", List[float], npt.NDArray[np.float64])