fix: added dokka and fix doc generation

[kikoso]

This PR fixes the doc generation, broken since 3.4.0.

JavaDoc does not like Kotlin, so we are updating it to a more modern documentation framework, Dokka. We are adding also a new flow to upload the documentation to the GitHub pages.

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• Appropriate docs were updated (if necessary)

Fixes #1248 🦕

[googlemaps-bot]

🎉 This PR is included in version 3.6.1 🎉

The release is available on:

• v3.6.1
• GitHub release

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