build(deps): bump helm-diff to v3.15.13 (#2788)

* build(deps): bump helm-diff to v3.15.13

Update helm-diff plugin version from v3.15.12 to v3.15.13 across
Dockerfiles, recommended version constant, CI matrix, and
integration test default.

Signed-off-by: yxxhero <aiopsclub@163.com>

* fix(ci): add golden files for helm-diff >= 3.15.13

helm-diff v3.15.13 omits null/empty labels and annotations keys from
diffs (databus23/helm-diff#1068), which broke the suppress-output-line-
regex integration test: the ValidatingWebhookConfiguration manifest no
longer renders a bare 'annotations:' key under metadata.

Add new golden files suffixed -after-helm-diff-3.15.13 (helm3, helm4,
live variants) and select them via version_ge in the test case, keeping
the existing 3.11.0 and pre-3.11.0 goldens for older plugin versions.

Signed-off-by: yxxhero <aiopsclub@163.com>

* refactor(test): drop legacy helm-diff golden files

CI only exercises the recommended helm-diff version, so replace the
version-suffixed golden files (-after-helm-diff-3.11.0,
-after-helm-diff-3.15.13) with a single set of base golden files
(diff, diff-live, diff-helm4, diff-live-helm4) containing the
v3.15.13 output, and remove the now-dead version gating.

Also drop the 'install semver' CI step, whose only consumer was the
removed gating.

Signed-off-by: yxxhero <aiopsclub@163.com>

* fix(test): remove helm-diff version gating from golden file selection

The previous commit deleted the version-suffixed golden files but the
selection gating was accidentally left behind, making the test reference
non-existent files for helm-diff >= 3.15.13.

Signed-off-by: yxxhero <aiopsclub@163.com>

---------

Signed-off-by: yxxhero <aiopsclub@163.com>

.github/workflows/ci.yaml

@@ -96,35 +96,35 @@ jobs:
           - helm-version: v3.18.6
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: ''
           # In case you need to test some optional helmfile features,
           # enable it via extra-helmfile-flags below.
           - helm-version: v3.18.6
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: '--enable-live-output'
           - helm-version: v3.22.0
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: ''
           - helm-version: v3.22.0
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: '--enable-live-output'
           # Helmfile now supports both Helm 3.x and Helm 4.x
           - helm-version: v4.3.0
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: ''
           - helm-version: v4.3.0
             kustomize-version: v5.8.0
             plugin-secrets-version: 4.7.4
-            plugin-diff-version: 3.15.12
+            plugin-diff-version: 3.15.13
             extra-helmfile-flags: '--enable-live-output'
     steps:
       - uses: actions/checkout@v7
@@ -146,8 +146,6 @@ jobs:
       - uses: actions/download-artifact@v8
         with:
           name: built-binaries-${{ github.run_id }}
-      - name: install semver
-        run: go install github.com/ffurrer2/semver/v2/cmd/semver@v2.12.0
       - name: Extract tar to get built binaries
         run: tar -xvf built-binaries.tar
       - name: Display built binaries