fix issue with double encoding of mqtt presigned urls

[daphid4]

Description

This fixes a bug found when using AWS presigned urls - the consensus is that the url was being double encoded and therefore always resulting in a 403

Related Issue

#643
https://community.hivemq.com/t/connect-mqtt-broker-with-pre-signed-url/751/8

Type of Change

• 📚 Examples / docs / tutorials / dependencies update
• 🔧 Bug fix (non-breaking change which fixes an issue)
• 🥂 Improvement (non-breaking change which improves an existing feature)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 🔐 Security fix

Checklist

• I've written tests (if applicable) for all new methods and classes that I created.
• I've added documentation as necessary so users can easily use and understand this feature/fix.

[cla-bot]

Thank you for your pull request and welcome to our community. We require contributors to sign our Contributor License Agreement, and we don't seem to have the users @daphid4 on file. In order for us to review and merge your code, please sign our Contributor License Agreement to get yourself added. You'll find the CLA and more information here: https://github.com/hivemq/hivemq-community/blob/master/CONTRIBUTING.adoc#contributor-license-agreement

[daphid4]

it looks like I'm not able to sign the cla

[lsiepel]

Gentle ping @Donnerbart could you have a look?