[FEATURE]: Add readiness probe

[shanduur]

Are you interested in contributing to the development of this feature?

Yes

Is your feature request related to a problem? Please describe.

N/A

Describe the solution you'd like.

Write a proposal/proof of concept, that will implement the custom readiness probe mechanism.

Describe alternatives you've considered.

N/A

Additional Information

• Directly related to #19 ;
• The desired library to use is hellofresh/health-go.