[central] ci/ghcr: containers still published when tests fail

[alxndrsn]

Observed

The container-publishing CI job ghcr.yml is independent of the testing job test.yml.

The result of this is that containers are published even when tests failed.

Expected

If tests fail, then container images should not be published to GHCR.

Examples

Examples are from master branch because github UI makes it much simpler to find by branch than find failures for tags, but the same issue likely occurs for tagged releases.

master / Merge pull request #1678 from getodk/hotfix/v2025.4.x

• test: https://github.com/getodk/central/actions/runs/22740902566
• publish: https://github.com/getodk/central/actions/runs/22740902591

master / Merge pull request #1569 from sadiqkhoja/v2025.4/update-news

• test: https://github.com/getodk/central/actions/runs/20245728326
• publish: https://github.com/getodk/central/actions/runs/20245728339

master / Merge pull request #881 from getodk/next

• test: https://github.com/getodk/central/actions/runs/15030379066
• publish: https://github.com/getodk/central/actions/runs/15030379059