PyPi package access from a workspace

[marrobi]

Part of feature #21

Description

As a Workspace User
I want to access python packages from PyPI
So that I can install python packages on a VM in a workspace

As a TRE Administrator
I want to configure Sonartype Nexus RM from outside of a workspace
So that I can configure package mirrors

As a Workspace Owner
I want to ensure that users cannot leak data from the workspace to Sonartype Nexus RM
So that no data is leaked

Acceptance Criteria

• Sonartype Nexus RM OSS optionally deployed within Shared Services using Terraform (https://hub.docker.com/_/sonatype-nexus)
• Administrator can manually configure a PyPI proxy (from outside a workspace) ( https://help.sonatype.com/repomanager3/formats/pypi-repositories#PyPIRepositories-ProxyingPyPIRepositories )
• User can use pip install to install a package on a VM within a workspace, e.g. pip install pandas ( https://help.sonatype.com/repomanager3/formats/pypi-repositories#PyPIRepositories-InstallingPyPIClientTools )
• No data can be uploaded from a workspace to Sonartype RM

Implementation

• [Task] Install Nexus as a shared service #518
• [Task] Add Nexus readme #519
• [Task] Disable default repos in Nexus #520