Prepdocs: Support additional args

[mattgotteiner]

Purpose

• Prepdocs scripts require certain environment variables to be set.
• Prepdocs has many additional arguments, and not all of them map to environment variables. For example, --removeall is used to delete documents from the search index.
• Support passing through these additional documents (e.g. ./prepdocs.ps1 --removall) without requiring environment variables.

Does this introduce a breaking change?

When developers merge from main and run the server, azd up, or azd deploy, will this produce an error?
If you're not sure, try it out on an old environment.

[X] Yes
[ ] No

Does this require changes to learn.microsoft.com docs?

This repository is referenced by this tutorial
which includes deployment, settings and usage instructions. If text or screenshot need to change in the tutorial,
check the box below and notify the tutorial author. A Microsoft employee can do this for you if you're an external contributor.

[ ] Yes
[X] No

Type of change

[ ] Bugfix
[X] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

[pamelafox]

Yay! I was hoping you'd make this change. Can you update the data_ingestion.md doc to say that the arguments can be passed directly?

[pamelafox]

I meant line 62/64, which has a convoluted instruction currently.

[mattgotteiner]

done

[pamelafox]

Ohh interesting, you still have to modify the file. It'd be nice to somehow change that in the future, as it's easy to accidentally not change it, and then remove actually operates on the whole glob, I think.