fetch openapispec files for indexing during prod deploy

[dmitrymatio]

Description

This is a temporary fix for missing openapispec during indexing step of build process.

We expect to move away from this soon with the migration to EDS.

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[jhodges10]

Thank you for taking care of this @dmitrymatio! This should solve our immediate issue blocking any indexing, and we'll revisit this in the future once we have an idea for how to index the actual contents of the API reference in more detail.