Disable unreliable Gitea Godot cache steps

Gitea cache restores were inconsistent and cache saves timed out or were
rejected as reserved by another job. Remove the cache steps and keep direct
4.7.2 downloads; document the evaluation and when to retry. The workflow is
otherwise clean (no .github/ci.yml exists).

docs/RELEASING.md

@@ -63,11 +63,12 @@ setup, so do not rely on it.
 > artifacts. If CI publishing fails again, run
 > `./tools/publish_release.sh <version>` from a checkout with `~/.git-credentials`.
 
-> **Godot cache:** the workflow uses Gitea Actions cache for the Godot binary and a
-> trimmed 4.7.2 export-template set (Linux/Windows/macOS/Web release files only, not
-> Android/iOS). The first run still downloads them; subsequent runs restore from cache.
-> If the host cache service is unavailable, remove the cache steps and let the install
-> steps download fresh copies.
+> **Godot cache evaluation:** Gitea Actions cache was tested for the Godot binary and
+> trimmed 4.7.2 templates. Restores worked intermittently, but cache saves timed out
+> in `CreateCacheEntry` / were rejected as reserved by another job. The cache steps
+> were removed because they added restore/save overhead without a reliable hit.
+> Revisit when the host's Gitea Actions cache service is healthy; otherwise keep
+> downloading the binary/templates directly.
 
 > The workflow lives in `.gitea/workflows/` (Gitea's canonical path). The old
 > `.github/workflows/ci.yml` was removed to avoid double runs on hosts that scan