Add merged json_encoders inheritance

[art049]

Change Summary

While inheriting the configuration , the json_encoders dictionaries are merged and the child classes can still override an encoder defined in the parent class.

Related issue number

Fixes #2024

Checklist

• Unit tests for the changes exist
• Tests pass on CI and coverage remains at 100%
• Documentation reflects the changes where applicable
• changes/<pull request or issue id>-<github username>.md file added describing change
  (see changes/README.md for details)

[codecov]

Codecov Report

Merging #2064 (3865c7b) into master (61bdba3) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master     #2064   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           23        23           
  Lines         4426      4426           
  Branches       888       888           
=========================================
  Hits          4426      4426           

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[samuelcolvin]

you need to add a change description and update the docs to describe the new behaviour preferably with an example

[samuelcolvin]

Suggested change

	json_encoders = {
	**getattr(parent_config, 'json_encoders', {}),
	**getattr(self_config, 'json_encoders', {}),
	}
	namespace['json_encoders'] = json_encoders
	namespace['json_encoders'] = {
	**getattr(parent_config, 'json_encoders', {}),
	**getattr(self_config, 'json_encoders', {}),
	}

[art049]

you need to add a change description and update the docs to describe the new behaviour preferably with an example

Thanks for the feedback @samuelcolvin !
I wasn't very sure this feature was ok as I didn't have any feedback neither on the issue nor the PR so I didn't complete it but as it seems ok to you I will be happy complete the changes 😄

[samuelcolvin]

@art049, I'm happy to accept this change.

We still need a change description and docs.

[samuelcolvin]

@art049 are you okay to fix this?

[art049]

@art049 are you okay to fix this?

@samuelcolvin yes, totally.
I fixed the code smell and added the required documentation 😄 .

WDYT about the docs? I don't know if it explains the feature properly enough

[samuelcolvin]

great, thank you so much.