Added servo example

[T3mplate-wow]

Description:

I needed some time to find out how to correct use a servo on the modul. I've seen that also other people had that problem. Thats why I added the way it works to the documentation.

Checklist:

• I am merging into next because this is new documentation that has a matching pull-request in esphome as linked above.
  or
• I am merging into current because this is a fix, change and/or adjustment in the current documentation and is not for a new component or feature.

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[github-actions]

There hasn't been any activity on this pull request recently. This pull request has been automatically marked as stale because of that and will be closed if no further activity occurs within 7 days. Thank you for your contributions.