(change) Check that all providers works without the field errorCode in the response

[thomaspoignant]

Motivation

It should be OK to consider there is no error if the relay proxy is not returning any errorCode in the evaluation response API.

Requirements

Check that if we remove the field from the response that all providers are working as expected:

• [x] Java
• [x] Javascript
• [x] Python
• [x] Kotlin
• [x] .Net
• [x] GO
• [x] Swift

[thomaspoignant]

I've opened a PR for the Java provider that was falling if errorCode was not provided: https://github.com/open-feature/java-sdk-contrib/pull/855

[thomaspoignant]

After doing so small changes we have checked that all providers are working without errorCode.