[Jupyter image] Fix installations to be done by notebook user

[Hedingber]

We noticed that when we installing certain packages (like nuclio-jupyter) that are already installed pip doesn't remove the old installation
Also when trying to manually uninstall them we got permission errors
The permission error happened because we're running the pip install in the docker file under the root user, and not the notebook user - fixed that
After some more playing with it I found out that pip doesn't automatically uninstall the package only on the first time and only when we're installing from git (i.e. just doing pip intsall to some older version does uninstall the old (newer) version, doing another installation after the first one from git does uninstall the old installation) not sure what's the cause for this after some help from @AlonMaor14 we found the reason - pip does not uninstall the old package is that when it pulls the code from git it checks its version - the version is the same as I have locally, so pip decides that no installation of the new code is actually needed and just use the old code 🤦 , you can see it by adding -vvv to the pip install
When I bumped the package version in my branch, everything worked like charm..
Another way to workaround it is adding -U to pip install