Update npm scripts

[mh-cbon]

This fix allows to run npm test on a non en-en system.

On my system localized in french, previous script always failed.

[[ -z $(git status -uno --porcelain) ]] checks that local files are committed.

[[ -z $(git cherry -v) ]] checks there is no pending commits to push.

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[mh-cbon]

won t sign the CLA, but you got the idea, right ?

[mh-cbon]

see also google/web-starter-kit#799 its another variation.

[evieluvsrainbows]

@mh-cbon you need to sign the CLA otherwise PRs won't be merged.

[mh-cbon]

nop sorry.