experimental[patch]: prompts import fix (#20534)

Replaced `from langchain.prompts` with `from langchain_core.prompts`
where it is appropriate.
Most of the changes go to `langchain_experimental`
Similar to #20348

libs/experimental/tests/integration_tests/chains/test_cpal.py

@@ -7,8 +7,8 @@ from unittest import mock
 
 import pytest
 from langchain.output_parsers import PydanticOutputParser
-from langchain.prompts.prompt import PromptTemplate
 from langchain_community.llms import OpenAI
+from langchain_core.prompts.prompt import PromptTemplate
 
 from langchain_experimental import pydantic_v1 as pydantic
 from langchain_experimental.cpal.base import (

libs/experimental/tests/integration_tests/chains/test_synthetic_data_openai.py

@@ -1,7 +1,7 @@
 import pytest
-from langchain.prompts.few_shot import FewShotPromptTemplate
 from langchain.pydantic_v1 import BaseModel
 from langchain_community.chat_models import ChatOpenAI
+from langchain_core.prompts.few_shot import FewShotPromptTemplate
 
 from langchain_experimental.tabular_synthetic_data.base import SyntheticDataGenerator
 from langchain_experimental.tabular_synthetic_data.openai import (

libs/experimental/tests/unit_tests/rl_chain/test_pick_best_chain_call.py

@@ -1,8 +1,8 @@
 from typing import Any, Dict
 
 import pytest
-from langchain.prompts.prompt import PromptTemplate
 from langchain_community.chat_models import FakeListChatModel
+from langchain_core.prompts.prompt import PromptTemplate
 from test_utils import MockEncoder, MockEncoderReturnsList
 
 import langchain_experimental.rl_chain.base as rl_chain

libs/experimental/tests/unit_tests/test_smartllm.py

@@ -1,7 +1,7 @@
 """Test SmartLLM."""
-from langchain.prompts.prompt import PromptTemplate
 from langchain_community.chat_models import FakeListChatModel
 from langchain_community.llms import FakeListLLM
+from langchain_core.prompts.prompt import PromptTemplate
 
 from langchain_experimental.smart_llm import SmartLLMChain