[148] - Healthcheck endpoint returns application/json content type

[bobstrecansky]

This is a draft to attempt to change the content type of the Healthcheck endpoint for this application from appliation/json to text/plain.

I don't currently have access to an environment where I can test this change, that's hindering me from validating this change.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[bobstrecansky]

I've also signed the CLA, but for some reason the bot is mentioning that I haven't. It might be due to my different naming convention for my PR (I use bobstrecansky-mc and bobstrecansky, not sure what the conventions are for this repo)

[bobstrecansky]

Closing in favor of : #368