[pgAdmin4][Patch]: Run MakeFile to generate builds in production mode

Hi,

When we run Webpack in production mode, it performs optimization on code
while in development we don't optimize generated JS and CSS bundles as dev
mode is for developer use.

So we should run Webpack bundle in production mode when we are generating
bundles for release mode.

*In the second patch:*

1) Enabled "*sourced maps*" in production mode as well which will help in
debugging issues.

2) Removed "*yarn run linter*" script when Webpack runs in production mode
because it is for developer only to check if there are any syntax errors in
JS modules.

3) Removed redundant script command "*yarn run bundle*" as "*yarn run
bundle:dev*" does the same thing.

Please find an attached patch.

Thanks,
Surinder