fix: Update license header pattern to match existing files

[cbartz]

Applicable spec: N/A

Overview

Update .licenserc.yaml to use pattern instead of content to correctly recognize existing license headers in the codebase.

Rationale

The license header check was failing with 19 invalid files (valid: 0, invalid: 19) even though all files have proper license headers in the format:

Copyright YYYY Canonical Ltd.
See LICENSE file for licensing details.

The issue was that the configuration used content which expects literal placeholders like [year] and [owner], but the actual files use specific years and "Canonical Ltd.". Using pattern with a regex allows matching the actual format.

Before:

content: |
  Copyright [year] [owner]
  See LICENSE file for licensing details.

After:

pattern: |
  Copyright \d{4} Canonical Ltd.
  See LICENSE file for licensing details.

Testing:

docker run apache/skywalking-eyes header check

• Before: valid: 0, invalid: 19, ignored: 57
• After: valid: 19, invalid: 0, ignored: 57

Juju Events Changes

None

Module Changes

None

Library Changes

None

Checklist

• The charm style guide was applied
• The contributing guide was applied
• The changes are compliant with ISD054 - Managing Charm Complexity
• The documentation for charmhub is updated - N/A (CI configuration only)
• The PR is tagged with appropriate label (urgent, trivial, complex)
• The CHANGELOG.md is updated with user-relevant changes. - N/A (CI configuration fix, not user-facing)

This is a trivial CI configuration fix that resolves failing license header checks.

[github-actions]

Unused entries in .trivyignore

Image: ghcr.io/canonical/content-cache:40d0c23bc44d72b8c11a7c8f4356c8c43e11d4ac-_latest_amd64

The following CVEs are in .trivyignore but not ignored by Trivy anymore:

• CVE-2025-47912
• CVE-2025-58186
• CVE-2025-58187
• CVE-2025-58188
• CVE-2025-61724

[cbartz]

No longer necessary