[Jupyter] fix 'update_demos.sh' path #2055

Job	Run time
Test charts	4m 21s
Helm Chart Install Sanity (coredns-updater)	4s
Helm Chart Install Sanity (dcgm-exporter)	6s
Helm Chart Install Sanity (dex-crds)	5s
Helm Chart Install Sanity (empty)	7s
Helm Chart Install Sanity (fuse-csi-driver)	9s
Helm Chart Install Sanity (gpu-feature-discovery)	6s
Helm Chart Install Sanity (iguazio-system)	10s
Helm Chart Install Sanity (mpi-operator)	8s
Helm Chart Install Sanity (node-feature-discovery)	9s
Helm Chart Install Sanity (pod-gpu-metrics-exporter)	9s
Helm Chart Install Sanity (prebaked-registry)	5s
Helm Chart Install Sanity (provazio)	8s
Helm Chart Install Sanity (pvc)	5s
Helm Chart Install Sanity (scaler)	9s
Helm Chart Install Sanity (spark-operator)	9s
Helm Chart Install Sanity (sparkoperator)	9s
Helm Chart Install Sanity (tenant)	9s
Helm Chart Install Sanity (tenant-creator)	9s
Helm Chart Install Sanity (tensorboard)	9s
Helm Chart Install Sanity (v3io-configs)	9s
Helm Chart Install Sanity (v3io-webapi)	5s
Helm Chart Install Sanity (v3iod)	6s
	7m 6s

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