pgAdmin 4 commit: Define the proper NODE_ENV environment during running

Define the proper NODE_ENV environment during running the webpack.
Using the webpack.DefinePlugin during the development build too, not
just in production build.

Fixes #2596.

Also - passing option 'warning: false' for UglifyJsPlugin, which will
not show warning messages on the console during the production build.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=2945b3fe93337174cd423367453621049980a0ae
Author: Surinder Kumar <surinder(dot)kumar(at)enterprisedb(dot)com>

Modified Files
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web/webpack.config.js | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)