[PROPOSAL]Make OSD plugin installation more flexible

[BionIT]

What/Why

What are you proposing?

A better mechanism to specify the plugins to install, schema to add, and address plugin version vs OSD version conflict

In a few sentences, describe the feature and its core capabilities.

What users have asked for this feature?

What problems are you trying to solve?

Allow specifying the plugin to install using plugin github repo ref in addition to just specify a downloadable url
Automatically resolve version conflict error by updating version in the package.json for the plugin during plugin build
Allow extra plugin config to be fed into build image workflow

What is the developer experience going to be?

Developer would just need to update the yaml file in order to change plugins to install and even specify path to additional configurations needed for that plugin

Are there any security considerations?

Are there any breaking changes to the API

NA

What is the user experience going to be?

Are there breaking changes to the User Experience?

Why should it be built? Any reason not to?

The feature implemented in #91 will create a workflow to build custom docker image and install plugins specified as secret - which are downloadable links. In order to use that feature, first of all, the plugin needs to be in the form of a downloadable link, then need to be added as secrets in github as an array. It is not super user friendly. Plus, OSD has historical issue with plugin version vs OSD version during plugin installation, and this mechanism should fix that.

What will it take to execute?

#60 would make this feature more easier to implement or using image override is still doable
proposed steps:

1. specify a schema to use in a yaml in order to add external plugins for installation: it can be similar to the build repo
2. implement logic to digest yaml file, and build the plugin artifact inside OSD using plugin helper or retrieve artifact from downloadable url
3. build docker image and push to repository

Any remaining open questions?