Fix typos in comments to core.services.yml and serialization.yaml

Problem/Motivation

This summary was updated based on #3552894-10: Fix typos in comments to core.services.yml and serialization.yaml to also include other typos.
The initial summary and fix only covered the DrupalKernel comment

Nitpick of the day:

There is a some comments in Drupal core that reference non-existing files or services

• reference to a non-existing file in the class comment of \Drupal\Core\DrupalKernel
• reference to a non-existing service in 2 Twig related classes

Steps to reproduce

• the file extension is wrong in
  • web/core/lib/Drupal/Core/DrupalKernel.php

  * CoreServiceProvider, which, in addition to registering any core services that
  * cannot be registered in the core.services.yaml file, adds any compiler passes

• the service name is wrong in
  • core/modules/help/src/HelpTopicTwigLoader.php
  • core/lib/Drupal/Core/Template/TwigEnvironment.php (2 times)

  // Note: always use \Drupal\Core\Serialization\Yaml here instead of the
  // "serializer.yaml" service. This allows the core serializer to utilize

Proposed resolution

• * CoreServiceProvider, which, in addition to registering any core services that
  * cannot be registered in the core.services.yml file, adds any compiler passes

• // Note: always use \Drupal\Core\Serialization\Yaml here instead of the
  // "serialization.yaml" service. This allows the core serializer to utilize

Remaining tasks

none

User interface changes

none

Introduced terminology

none

API changes

none

Data model changes

none

Release notes snippet

none