chore: Add Azure Linux (AZL) source to production (#5175)

## Overview

Add Azure Linux (AZL) as a source in the production instance of osv.dev.
Microsoft publishes OSV-format advisories at
[microsoft/AzureLinuxVulnerabilityData](https://github.com/microsoft/AzureLinuxVulnerabilityData),
and the ecosystem already has full support in the codebase.

Closes #5041

## Details

Adds an `azurelinux` entry to source.yaml. It's a Git-based source (type
0) that pulls `AZL-`-prefixed JSON files from the osv directory of
Microsoft's repo. The repo has around 12,000 advisories and is updated
automatically a few times a day.

The equivalent entry was previously added to source_test.yaml and tested
on the staging instance.

## Testing

- Verified the import worked correctly on the test instance via
source_test.yaml before promoting to production.
- Confirmed the repo structure, file prefix (`AZL-`), directory (osv),
and extension (`.json`) match the upstream repo.
- Checked that the entry follows the same pattern as other Git-based
sources like `almalinux`, `bellsoft`, and `psf`.

Co-authored-by: Rex P <106129829+another-rex@users.noreply.github.com>

Author: JamieMagee

source.yaml

@@ -72,6 +72,20 @@
   editable: False
   strict_validation: True
 
+- name: 'azurelinux'
+  versions_from_repo: False
+  type: 0
+  ignore_patterns: ['^(?!AZL-).*$']
+  directory_path: 'osv'
+  repo_url: 'https://github.com/microsoft/AzureLinuxVulnerabilityData.git'
+  detect_cherrypicks: False
+  extension: '.json'
+  db_prefix: ['AZL-']
+  ignore_git: False
+  link: 'https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/'
+  editable: False
+  strict_validation: True
+
 - name: 'bellsoft'
   versions_from_repo: False
   type: 0