Use Retry-After Header instead of ambiguous back-off strategy for Management API requests

[nkooman-bzs]

Motivation

Provides better handling for retry attempts.
https://kontent.ai/learn/docs/apis/openapi/management-api-v2/#section/Rate-limiting

Proposed solution

Keep the same retry strategy option for other consumers of the core SDK.
Optionally check for Retry-After header in response.

Additional context

https://github.com/kontent-ai/core-sdk-js/blob/master/lib/http/http.functions.ts

[Enngage]

We're just starting with the overall modernization / refactoring of the SDKs and will keep this in mind:) I'll leave it open so we don't forget.

[Enngage]

Looking at the current code, it should already be using the Retry-after header

core-sdk-js/lib/helpers/retry-helper.ts

Line 153 in b4f54ba

const retryValueHeader = headers.find(

[Enngage]

This is also implemented in the upcoming modernization - #50