[Feature] Trigger speedtest with API

[svenvg93]

📃 Description

This PR adds a option to trigger the speedtest via the API

Default return message:

{
    "data": {
        "id": 494
    },
    "message": "Speedtest started."
}

📖 Documentation

Add a link to the PR for documentation changes.

🪵 Changelog

➕ Added

• /api/v1/speedtests to start a speedtest with the CLI auto select
  - ?server_id=1234 start a speedtest with specifying the server id
  - ?await=true to wait for the speedtest and return the results in the answer

🔧 Fixed

• closes Remotely trigger speedtests #1047

📷 Screenshots

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