Add jq and telnet

[mabe443]

Hi @jjethwa it would be great if you could integrate jq and telnet into your image.

I have made the following changes in this pull request:

• add jq
• add telnet

These changes work fine for me in the x86_64 environment. ARM environment was not tested.

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Justification

• jq is needed to run the plugin check_prometheus_metric.sh. (if you use prometheus)
• telnet is needed to test if ports are reachable. This makes testing much easier.

[jjethwa]

Thanks, @mabe443 😃 I agree that those would be useful to have in the image