build(javadoc): skip examples module from Javadoc

[mojito317]

PR summary

fixes #512

Note: An existing issue is required before opening a PR.

PR Checklist

Please make sure that your PR fulfills the following requirements:

• The commit message follows the
  Angular Commit Message Guidelines.
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• New tests
• Build/CI related changes
• Documentation content changes
• Other (please describe)

What is the current behavior?

Javadoc displays features on main page.

What is the new behavior?

Javadoc does not display features on main page.

Does this PR introduce a breaking change?

• Yes
• No

Other information

I tested this locally and now I cannot see it: