change namespace surfix to random string (#637)

Signed-off-by: Yingchun Guo <yingchun.guo@intel.com>

Author: daisy-ycguo

.github/workflows/_gmc-e2e.yml

@@ -45,7 +45,7 @@ jobs:
         run: |
           echo "IMAGE_REPO=$OPEA_IMAGE_REPO" >> $GITHUB_ENV
           lower_example=$(echo "${{ inputs.example }}" | tr '[:upper:]' '[:lower:]')
-          echo "APP_NAMESPACE=$lower_example-$(date +%Y%m%d%H%M%S)" >> $GITHUB_ENV
+          echo "APP_NAMESPACE=$lower_example-$(tr -dc A-Za-z0-9 </dev/urandom | head -c 16)" >> $GITHUB_ENV
           echo "ROLLOUT_TIMEOUT_SECONDS=1800s" >> $GITHUB_ENV
           echo "KUBECTL_TIMEOUT_SECONDS=60s" >> $GITHUB_ENV
           echo "continue_test=true" >> $GITHUB_ENV

.github/workflows/_manifest-e2e.yml

@@ -54,7 +54,7 @@ jobs:
           echo "IMAGE_REPO=$OPEA_IMAGE_REPO" >> $GITHUB_ENV
           echo "IMAGE_TAG=${{ inputs.tag }}" >> $GITHUB_ENV
           lower_example=$(echo "${{ inputs.example }}" | tr '[:upper:]' '[:lower:]')
-          echo "NAMESPACE=$lower_example-$(date +%Y%m%d%H%M%S)" >> $GITHUB_ENV
+          echo "NAMESPACE=$lower_example-$(tr -dc A-Za-z0-9 </dev/urandom | head -c 16)" >> $GITHUB_ENV
           echo "ROLLOUT_TIMEOUT_SECONDS=1800s" >> $GITHUB_ENV
           echo "KUBECTL_TIMEOUT_SECONDS=60s" >> $GITHUB_ENV
           echo "continue_test=true" >> $GITHUB_ENV