[Py OV] Update samples with import from openvino directly (openvinoto…

…olkit#28341)

### Details:
 - Replace `openvino.runtime` with `openvino` in samples
 

### Tickets:
 - [CVS-159526](https://jira.devtools.intel.com/browse/CVS-159526)

Signed-off-by: Alicja Miloszewska <alicja.miloszewska@intel.com>

samples/python/benchmark/bert_benchmark/bert_benchmark.py

@@ -11,7 +11,7 @@
 
 import openvino as ov
 import datasets
-from openvino.runtime import get_version
+from openvino import get_version
 from transformers import AutoTokenizer
 from transformers.onnx import export
 from transformers.onnx.features import FeaturesManager

samples/python/benchmark/sync_benchmark/sync_benchmark.py

@@ -10,8 +10,8 @@
 
 import numpy as np
 import openvino as ov
-from openvino.runtime import get_version
-from openvino.runtime.utils.types import get_dtype
+from openvino import get_version
+from openvino.utils.types import get_dtype
 
 
 def fill_tensor_random(tensor):

samples/python/benchmark/throughput_benchmark/throughput_benchmark.py

@@ -10,8 +10,8 @@
 
 import numpy as np
 import openvino as ov
-from openvino.runtime import get_version
-from openvino.runtime.utils.types import get_dtype
+from openvino import get_version
+from openvino.utils.types import get_dtype
 
 
 def fill_tensor_random(tensor):

samples/python/model_creation_sample/model_creation_sample.py

@@ -9,7 +9,7 @@
 
 import numpy as np
 import openvino as ov
-from openvino.runtime import op, opset1, opset8
+from openvino import op, opset1, opset8
 
 from data import digits