Add Readdy test custom domain template

[benn-zh]

Description

Add a new readdy domain service provider template.

Type of change

Please mark options that are relevant.

• New template
• Bug fix (non-breaking change which fixes an issue in the template)
• New feature (non-breaking change which adds functionality to the template)
• Breaking change (fix or feature that would cause existing template behavior to be not backward compatible)

How Has This Been Tested?

Please mark the following checks done

• Schema validated using JSON Schema template.schema
• Template functionality checked using Online Editor
• Template is checked using template linter
• Template file name follows the pattern <providerId>.<serviceId>.json

Example variable values

None

[github-actions]

Linter OK:

Linter result for readdy.ai.website-test.json

[kerolasa]

Look acceptable. To get rid of linter warning you could add the following to the template: "shared": true,

[pawel-kow]

@benn-zh please fill in PR description as per template

[benn-zh]

@benn-zh please fill in PR description as per template

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