Fix dgbuilder image runtime dependencies

Move npm install into docker build phase, where it should be. Due to the
nature of the upstream project (node-RED) there can be still some
runtime dependencies - it depends on the use-case.

Issue-ID: CCSDK-1117
Signed-off-by: Petr Ospalý <p.ospaly@partner.samsung.com>
Change-Id: I2abda871b880d8323de186dba04f2d1d92ab7622
2 files changed