Sanitize bicep indentifiers

[eerhardt]

Description

When we create resources in bicep, we need to ensure the identifier name we use is valid. One common complication is that Aspire resources only allow letters, numbers and a hyphen. But bicep doesn't allow hyphen, but instead an underscore.

Add a new convenience API to get a bicep identifier from an IAzureResource.

Fix https://github.com/dotnet/aspire/issues/6074

Checklist

• Is this feature complete?
  • [x] Yes. Ready to ship.
• Are you including unit tests for the changes and scenario tests if relevant?
  • [x] Yes
• Did you add public API?
  • [x] Yes
    • If yes, did you have an API Review for it?
      • [x] No
    • Did you add <remarks /> and <code /> elements on your triple slash comments?
      • [x] No
• Does the change make any security assumptions or guarantees?
  • [x] No
• Does the change require an update in our Aspire docs?
  • [x] No

Microsoft Reviewers: Open in CodeFlow