Change the configuration location of the app to the primary API

[davidsmonkeys]

Description

• Remove the function app
• Define the build items to specify the API location
• Update the code to use the environment variable
• Add the API location to allowed domains
• Update the pipelines to not build the function app
• Update the pipelines to do the custom build
• Explicitly prevent pipeline run on pull request

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• [X] New feature (non-breaking change which adds functionality)

How Has This Been Tested?

We have validated that this works in the local environment and the API changes have already been deployed and are being used by the Web App. As such I'm reasonably confident that this will also correctly retrieve the settings from the API when deployed.

Checklist:

• [X] My code follows the style guidelines of this project
• [X] I have performed a self-review of my own code
• [X] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published in downstream modules

[davidsmonkeys]

Following this merge we need to create the pipeline for deploying the app in Azure Dev Ops to target the YAML pipeline