Upgrade Gitea test infrastructure from v1.17.1 to latest

[vdemeester]

Description

The Gitea instance used in the git resolver e2e tests (test/git-resolver/gitea.yaml) is pinned to v1.17.1 (July 2022), which is 8 major versions behind the current release (v1.25.4, January 2026). The Helm chart it was generated from (v6.0.0) is also far behind the current v12.5.0.

What needs updating

Component	Current	Latest
Gitea server image	mirror.gcr.io/gitea/gitea:1.17.1	1.25.x
Helm chart (source of gitea.yaml)	v6.0.0	v12.5.0
Gitea Go SDK (code.gitea.io/sdk/gitea)	v0.21.0	Verify compatibility

Context

The gitea.yaml was originally generated via helm template gitea gitea-charts/gitea and committed as a static file. The Helm chart has since been significantly restructured. The tests were disabled in 5f38010 (Sep 2025) because the chart had changed, and are being re-enabled in #9442.

Suggested approach

1. Regenerate test/git-resolver/gitea.yaml from the current gitea-charts/gitea Helm chart
2. Update the Gitea image references to 1.25.x
3. Verify the admin user API, token creation API (the sha1 field in the token response may have changed), and file creation API still work with the setupGitea helper in test/resolvers_gitea_test.go
4. Bump the Go SDK if needed for compatibility

Affected files

• test/git-resolver/gitea.yaml — static Helm chart output
• test/resolvers_gitea_test.go — setupGitea() function that calls Gitea APIs
• go.mod — Gitea SDK version (if bump needed)

Related

• Add Gitea e2e tests to CI #9442 — re-enables the Gitea e2e tests in CI