Update azure/setup-helm action to v4 (#15)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yaml

@@ -59,7 +59,7 @@ jobs:
       uses: actions/checkout@v5
 
     - name: Set up Helm
-      uses: azure/setup-helm@v3
+      uses: azure/setup-helm@v4
       with:
         version: '3.12.0'
 

.github/workflows/release.yaml

@@ -29,7 +29,7 @@ jobs:
         go-version: '1.25'
 
     - name: Set up Helm
-      uses: azure/setup-helm@v3
+      uses: azure/setup-helm@v4
       with:
         version: '3.12.0'
 
@@ -109,7 +109,7 @@ jobs:
       uses: actions/checkout@v5
 
     - name: Set up Helm
-      uses: azure/setup-helm@v3
+      uses: azure/setup-helm@v4
       with:
         version: '3.12.0'