Add publication demo content

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User Story(s)

• As a Developer, I'd like to have access to a variety of demo publication content, in order to test and develop new publication functionalities effectively.
• As a Tester, I'd like to easily interact with different types of publication content, so that I can ensure the robustness and versatility of the publication features.

Conditions of Satisfaction

• Should include 10 pieces of varied publication content to demonstrate different construction types.
• Should aim to save time in setting up and testing publications for developers and testers.
• Should ensure that publications are treated as a first-class content type within the platform.
• Should be enabled by default in the az_demo environment for immediate accessibility and testing.