[tests-only][full-ci] Test: run Core-API-8 test suite on k8s

[anon-pradip]

Description

Enables Unicode text preview support for the thumbnails service in Kubernetes and ensures consistent thumbnail generation between test builds and production images.

Problem

1. K8s deployments: Thumbnails service couldn't render Unicode characters (e.g., Devanagari script) due to missing fonts
2. Inconsistent test builds: Test builds used standard Go image/jpeg encoder while production Docker images (built with ENABLE_VIPS=true) use libvips encoder, causing different JPEG output and test failures

Changes

• K8s font support: Added ConfigMaps for NotoSans font and font configuration, mounted into thumbnails deployment
• Consistent test builds: Added ENABLE_VIPS=true to test builds to match production images (which already have VIPS enabled)
• Fixtures: Updated 5 preview fixtures to match VIPS output (JPEG with EXIF metadata):
  • unicode-fixture.png: 620 → 739 bytes
  • fit.png: 713 → 885 bytes
  • fill.png: 874 → 1029 bytes
  • resize.png: 829 → 984 bytes
  • thumbnail.png: 874 → 1029 bytes

Note

Production Docker images have been built with ENABLE_VIPS=true. This PR ensures test builds use the same encoder.

Related Issue

• Part of: [QA] Fix failing tests on suites running on k8s #11658

Motivation and Context

How Has This Been Tested?

• test environment:
• test case 1:
• test case 2:
• ...

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud