Draft: Refactoring Dockerfile for DBLab Engine plugin

In this Merge Request, we have refactored the Dockerfile to address an issue where certain files required by the Netdata service were not being copied to the correct locations upon container startup.

Previously, our Dockerfile was structured to copy these files at build time, which wasn't reliable due to a conflicting script in the Netdata base image that also copies files at startup.

To solve this, we've created a new entry script start.sh which runs the original run.sh script in the background, waits for a brief period to ensure the stock configuration has been copied, and then copies our custom configuration files to the correct locations. This ensures that our custom configurations are preserved and Netdata functions as expected.

Fixed:

Copying stock configuration to /etc/netdata
cp: not replacing '/etc/netdata/edit-config'
cp: not replacing '/etc/netdata/netdata-updater.conf'
cp: not replacing '/etc/netdata/netdata.conf'
cp: not replacing '/etc/netdata/orig'