switch back to helm 3 as the helm-schema plugion fails during helm 4 default plugin verification (is not signed)

On-behalf-of: Gerald Morrison (SAP) <gerald.morrison@sap.com>
Signed-off-by: Gerald Morrison (SAP) <gerald.morrison@sap.com>

Author: morrison-sap

.github/workflows/controller-release.yml

@@ -292,7 +292,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4 # v4
         with:
-          version: v4.1.3
+          version: v3.20.1
 
       - name: Download RC chart artifact
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7

.github/workflows/kubernetes-controller.yml

@@ -85,7 +85,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4 # v4
         with:
-          version: v4.1.3
+          version: v3.20.1
 
       - name: Generate values schema
         working-directory: ${{ env.LOCATION }}
@@ -152,7 +152,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4 # v4
         with:
-          version: v4.1.3
+          version: v3.20.1
 
       - name: Compute VERSION
         id: version
@@ -268,7 +268,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4 # v4
         with:
-          version: v4.1.3
+          version: v3.20.1
 
       - name: Download build artifacts
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7
@@ -361,7 +361,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4 # v4
         with:
-          version: v4.1.3
+          version: v3.20.1
 
       - name: Log in to GHCR
         uses: docker/login-action@c94ce9fb468520275223c153574b00df6fe4bcc9 # v3