build: run vsce package during testing

This will detect npm dependency issues that are detected during
packaging.

Change-Id: I7e3bbeee407b764a18e80a21999385472812cf08
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/279012
Trust: Hyang-Ah Hana Kim <[email protected]>
Run-TryBot: Hyang-Ah Hana Kim <[email protected]>
TryBot-Result: kokoro <[email protected]>
Reviewed-by: Suzy Mueller <[email protected]>

Author: hyangah

build/Dockerfile

@@ -27,6 +27,7 @@ ENV PATH /workspace/vscodego/go/bin:/go/bin:/usr/local/go/bin:${PATH}
 ENV DEBIAN_FRONTEND noninteractive
 
 RUN apt-get update && apt-get install -y libnss3 libgtk-3-dev libxss1 libasound2 xvfb libsecret-1-0
+RUN npm install -g vsce
 
 WORKDIR /workspace
 ENTRYPOINT ["build/all.bash"]

build/all.bash

@@ -52,6 +52,9 @@ run_test() {
 
   echo "**** Run settings generator ****"
   go run tools/generate.go -w=false
+
+  echo "**** Check if vsce works ****"
+  vsce package
 }
 
 run_test_in_docker() {