Install and use ruff format instead of black for code formatting. (#12585)

Best to review one commit at a time, since two of the commits are 100%
autogenerated changes from running `ruff format`:
- Install and use `ruff format` instead of black for code formatting.
- Output of `ruff format .` in the `langchain` package.
- Use `ruff format` in experimental package.
- Format changes in experimental package by `ruff format`.
- Manual formatting fixes to make `ruff .` pass.

libs/experimental/langchain_experimental/tabular_synthetic_data/openai.py

@@ -16,7 +16,7 @@ def create_openai_data_generator(
     llm: ChatOpenAI,
     prompt: BasePromptTemplate,
     output_parser: Optional[BaseLLMOutputParser] = None,
-    **kwargs: Any
+    **kwargs: Any,
 ) -> SyntheticDataGenerator:
     """
     Create an instance of SyntheticDataGenerator tailored for OpenAI models.