Add user-assigned identity credential options to Bicep configuration

[shenglol]

The PR adds the following Bicep configuration section to support authentication using user-assigned identities:

{
  "cloud": {
    "currentProfile": "AzureCloud",
+   "credentialOptions": {
+      "managedIdentity": {
+        "type": "SystemAssigned | UserAssigned",
+        "clientId": "User-assigned identity cliend ID",
+        "resourceId": "User-assigned identity resource ID"
+      }
+    }
  }
}

Fixes #12185.

Microsoft Reviewers: Open in CodeFlow

[github-actions]

Test this change out locally with the following install scripts (Action run 6635351575)

VSCode

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-vsix.sh) --run-id 6635351575

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-vsix.ps1) } -RunId 6635351575"

Azure CLI

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-cli.sh) --run-id 6635351575

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-cli.ps1) } -RunId 6635351575"

[github-actions]

Test Results

     132 files  ±  0       132 suites  ±0   4h 2m 28s ⏱️ - 8m 38s
10 669 tests +  9  10 669 ✔️ +  9  0 💤 ±0  0 ❌ ±0 
51 563 runs  +36  51 563 ✔️ +36  0 💤 ±0  0 ❌ ±0 

Results for commit ee2de39. ± Comparison against base commit aeef173.