fix(large-scale-notification): replace invalid DefaultAzureCredential option with az login auth flow

[Copilot]

requiredEnvVars is not a valid DefaultAzureCredentialOptions property, and AZURE_TOKEN_CREDENTIALS has no meaning in Azure Identity. The script silently accepted the invalid option while the README pointed users at a non-functional env var.

Changes

• script/mockInstallationData.ts: Remove the invalid requiredEnvVars option from DefaultAzureCredential

  // before
  const credential = new DefaultAzureCredential({
    requiredEnvVars: ["AZURE_TOKEN_CREDENTIALS"],
  });
  
  // after
  const credential = new DefaultAzureCredential();

• README.md: Replace the instruction to set AZURE_TOKEN_CREDENTIALS=dev with the correct guidance to run az login, which is the supported auth flow for DefaultAzureCredential in local/script contexts

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• learn.microsoft.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)