chore(ci): update GitHub Actions dependencies to latest versions

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/goreleaser.yml

@@ -23,7 +23,7 @@ jobs:
           go-version: "^1"
 
       - name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v6
+        uses: goreleaser/goreleaser-action@v7
         with:
           # either 'goreleaser' (default) or 'goreleaser-pro'
           distribution: goreleaser

.github/workflows/stable.yml

@@ -71,12 +71,12 @@ jobs:
 
       - run: echo hello > world.txt
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v7
         with:
           name: my-artifact
           path: world.txt
 
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v8
         with:
           name: my-artifact
           path: distfiles

.github/workflows/testing.yml

@@ -71,12 +71,12 @@ jobs:
 
       - run: echo hello > world.txt
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v7
         with:
           name: my-artifact
           path: world.txt
 
-      - uses: actions/download-artifact@v5
+      - uses: actions/download-artifact@v8
         with:
           name: my-artifact
           path: distfiles