Remove unnecessary files and subheaders in documentation

docs/source/hooks/index.md

@@ -1,8 +1,5 @@
 # Hooks
 
-
-## Introduction
-
 Hooks are a mechanism to add extra behaviour to Kedro's main execution in an easy and consistent manner. Some examples might include:
 
 * Adding a log statement after the data catalog is loaded.

docs/source/nodes_and_pipelines/run_a_pipeline.md

@@ -48,8 +48,6 @@ kedro run --runner=ThreadRunner
 
 For more information on how to maximise concurrency when using Kedro with PySpark, please visit our guide on [how to build a Kedro pipeline with PySpark](../integrations/pyspark_integration.md).
 
-hook_manager: PluginManager = None,
-
 ## Custom runners
 
 If the built-in Kedro runners do not meet your requirements, you can also define your own runner within your project. For example, you may want to add a dry runner, which lists which nodes would be run without executing them:

docs/source/tutorial/spaceflights_tutorial.md

@@ -4,9 +4,6 @@ In this tutorial, we construct nodes and pipelines for a price-prediction model
 
 The tutorial takes approximately **30 minutes** to complete. You will work in the terminal and by inspecting project files in an IDE or text editor. There is no Jupyter notebook for the project.
 
-
-## Scenario
-
 *It is 2160, and the space tourism industry is booming. Globally, thousands of space shuttle companies take tourists to the Moon and back. You have been able to source data that lists the amenities offered in each space shuttle, customer reviews, and company information.*
 
 ***Project***: *You want to construct a model that predicts the price for each trip to the Moon and the corresponding return flight.*