Fix security issues for helm test workflow (opea-project#1908)

Signed-off-by: ZePan110 <ze.pan@intel.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Signed-off-by: cogniware-devops <ambarish.desai@cogniware.ai>

Author: 2 people

.github/workflows/_helm-e2e.yml

@@ -2,7 +2,9 @@
 # SPDX-License-Identifier: Apache-2.0
 
 name: Helm Chart E2e Test For Call
-permissions: read-all
+permissions:
+  contents: read
+
 on:
   workflow_call:
     inputs: