Duplicate of #45325 that targets 13.3.x

The purpose of the changes is to clean all markdown to match a single pedantic style.

• To ensure all changes in style are properly separated.

• To ensure all styled content aligns to nearest 4-character-tab.

• To ensure all code blocks use the Angular <code-example> or <code-tab> elements.

• To ensure all markdown exists outside of html tags.

• To ensure all images use the Angular style for <img> elements.

• To ensure that all smart punctuation is replaced or removed.

  ’, ’, “, ”, –, —, …
  

• To ensure all content does not conflict with the following reserved characters.

  @, $, *, &, #, |, <, >,
  

• To ensure all content displays using html entities.

The following changes were made to files in the following directory.

aio/content

The target files were markdown files.
The list of excluded files:

.browserslistrc, .css, .conf, .editorconfig, .gitignore, .html, .js, .json, .sh, .svg, .ts, .txt, .xlf,

PR Checklist

• The commit message follows our guidelines: https://github.com/angular/angular/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• angular.io application / infrastructure changes
• Other... Please describe: Documentation markdown formatting.

What is the current behavior?

Updating markdown to be consistent across the docs.

Does this PR introduce a breaking change?

• Yes
• No