upgrade node image version from 12 to 16

Signed-off-by: Siyuan Tian <[email protected]>

Dockerfile

@@ -20,7 +20,7 @@ COPY --from=fetch-kubeflow-kubeflow $BACKEND_LIB .
 RUN python setup.py sdist bdist_wheel
 
 # --- Build the frontend kubeflow library ---
-FROM node:12-buster-slim AS frontend-kubeflow-lib
+FROM node:16-buster-slim AS frontend-kubeflow-lib
 
 WORKDIR /src
 
@@ -32,7 +32,7 @@ COPY --from=fetch-kubeflow-kubeflow $LIB/ ./
 RUN npm run build
 
 # --- Build the frontend ---
-FROM node:12-buster-slim AS frontend
+FROM node:16-buster-slim AS frontend
 
 WORKDIR /src
 COPY ./frontend/package*.json ./