ci: Use correct robot user

Author: Techassi

.github/workflows/build.yaml

@@ -192,8 +192,8 @@ jobs:
         uses: stackabletech/actions/publish-helm-chart@29bea1b451c0c2e994bd495969286f95bf49ed6a # TODO: Use released action
         with:
           chart-registry-uri: oci.stackable.tech
-          chart-registry-username: robot$sdp+github-action-build
-          chart-registry-password: ${{ secrets.HARBOR_ROBOT_SDP_GITHUB_ACTION_BUILD_SECRET }}
+          chart-registry-username: robot$sdp-charts+github-action-build
+          chart-registry-password: ${{ secrets.HARBOR_ROBOT_SDP_CHARTS_GITHUB_ACTION_BUILD_SECRET }}
           chart-repository: sdp-charts
           chart-directory: deploy/helm/${{ env.OPERATOR_NAME }}
           chart-version: ${{ needs.build-container-image.outputs.operator-version }}