AR-1142 - refactor install_docker to be based on the family

[jfcabral]

Hi

Motivation This PR was initially motivated by the issue https://armbian.atlassian.net/browse/AR-1142

Upon checking the code, I've noticed it was not exactly as mentioned in the issue https://github.com/armbian/config/blob/c9a9b494c3069807471bb00c0336566cd186f6d9/debian-software#L649 Still, I believe there was yet room for improvement, thus this PR 😄

After reviewing the install_docker function, I've noticed that it is still tied to specific Debian/Ubuntu versions. In my opinion this is not desired, as will require further maintenance in the future, in order to support newer linux versions.

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Changes

1. I've changed the logic of the referred function so it works based on the linux family, thus following the official docker install guidelines. This will, hopefully, ensure that it will be able to install Docker against any current AND future Debian/Ubuntu versions, without any further changes
   • Debian: https://docs.docker.com/engine/install/debian/#install-using-the-repository
   • Ubuntu: https://docs.docker.com/engine/install/ubuntu/#install-using-the-repository
2. I've restructured the function code in order to remove some duplicated statements

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Tests

Installation of Docker, using the tool on a freshly installed:

• ✅ Ubuntu 22.04.1 (jammy)
• ✅ Ubuntu 18.04.5 (bionic) - proving it is not only forward compatible, but also backwards compatible 😄

Note: In order to speed-up the test process, I've done both tests using WSL2 on Windows 10 (AMD64). I know it's not ideal, but I believe the code, as is, should be independent from the HW architecture.

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If you have any question, feedback or suggestion, please do not hesitate to say so :) Thank you