ci: update deprecated GitHub Actions to v4/v6

Author: MimoJanra

.github/workflows/build-release.yml

@@ -43,9 +43,9 @@ jobs:
             output: testops-mcp-linux-arm64
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v6
         with:
           go-version: '1.26'
 
@@ -58,7 +58,7 @@ jobs:
           go build -o build/releases/${{ matrix.output }} ./cmd/server/main.go
 
       - name: Upload artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: ${{ matrix.output }}
           path: build/releases/${{ matrix.output }}
@@ -71,10 +71,10 @@ jobs:
       contents: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Download all artifacts
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           path: artifacts