test: fix filenames (#770)

they need to end with `-values.yaml`

Reviewed-on: https://code.forgejo.org/forgejo-helm/forgejo-helm/pulls/770
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Co-committed-by: Michael Kriese <michael.kriese@visualon.de>

ci/single-values.yml

@@ -1,23 +0,0 @@
-redis-cluster:
-  enabled: false
-postgresql:
-  enabled: true
-postgresql-ha:
-  enabled: false
-
-persistence:
-  enabled: true
-
-gitea:
-  config:
-    database:
-      DB_TYPE: postgres
-    session:
-      PROVIDER: db
-    cache:
-      ADAPTER: memory
-    queue:
-      TYPE: level
-    indexer:
-      ISSUE_INDEXER_TYPE: bleve
-      REPO_INDEXER_ENABLED: true