Automate generating terraform configs README files

[kron4eg]

What type of PR is this?
/kind documentation

What this PR does / why we need it:

• To avoid forgetting to update the README file of the corresponding terraform config now we will fail the CI (verify-codegen).
• Formalize the procedure of terraform config README generation

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Automate generating terraform configs README files

[adeniyistephen]

looks good to me.

[ahmedwaleedmalik]

/approve ⭐

[kubermatic-bot]

LGTM label has been added.

Git tree hash: 6173243f1b590b9c5a277f2cc0b8973c475ec9be

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ahmedwaleedmalik

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