idt-installer - support for Linux Mint distributions

[taufort]

Summary
The idt-installer fails on Linux Mint distribution.

Steps to reproduce
(include tooling version, platform, etc)

1. curl -sL https://ibm.biz/idt-installer | bash

Operating System
Specify: (MacOS, Linux, Windows)
Linux Mint. In my case, it was Linux Mint 19.3:

$ cat /etc/os-release 
NAME="Linux Mint"
VERSION="19.3 (Tricia)"
ID=linuxmint
ID_LIKE=ubuntu
PRETTY_NAME="Linux Mint 19.3"
VERSION_ID="19.3"
HOME_URL="https://www.linuxmint.com/"
SUPPORT_URL="https://forums.ubuntu.com/"
BUG_REPORT_URL="http://linuxmint-troubleshooting-guide.readthedocs.io/en/latest/"
PRIVACY_POLICY_URL="https://www.linuxmint.com/"
VERSION_CODENAME=tricia
UBUNTU_CODENAME=bionic

Supporting details
(Logs, stack traces, images, etc. Wrap in <detail> ... </detail> tags as appropriate)

$ curl -sL https://ibm.biz/idt-installer | bash
[main] --==[ IBM Cloud Developer Tools for Linux/MacOS - Installer, v1.2.3 ]==--
[main] WARN: Linux has only been tested on Ubuntu, RedHat, Centos, Debian and Fedora distrubutions please let us know if you use this utility on other Distros
[install] Starting Update...
[install] Note: You may be prompted for your 'sudo' password during install.
[install_deps] ERROR: This script has not been updated for use with your linux distribution (Linux Mint 19.3 Tricia)

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Development "done" checklist

• Add support in code
• Test case to verify
• Public Documentation updated
• Change added to "release notes" as appropropriate
• Notification to stakeholders (OM, other squads, etc)