Restrict onbuild trigger to only add ./src/Pyz
Restrict onbuild trigger to only add ./src/Pyz

If you add `./src/Orm` and `./src/Generated` to the Image via onbuild
trigger, then you will have odd and outdated artifacts in the image
which will break the init process esp. the propel migration due to
seemingly pending migration tasks.

claranet/spryker-base,claranet/spryker-base,claranet/spryker-base