Investigate how to reduce plugin size after adding Spring artifacts

[EgorkaKulikov]

Description

There is a requirement to have a limited plugin size. Dima recommended to be limited by 100 Mb

Current implementation of Spring support increased plugin size up to 60 Mb
35 Mb here #2085
24 Mb here #2125
More than that, now we pack just one version of Spring Boot to our shadow jar. It may not be enough sometimes.

We should think about an approach to reduce plugin with Spring support distributive size.

Expected behavior

To begin with, let's describe the approach in issue. May be it will be implemented later.

Potential alternatives

We can separate UtBot into two plugins:

• Java + Spring editions (without Python, Js and other experimental features)
• Standard edition without Spring

The size of both editions will be not very big.

Context

Implementation will be required to the next release of whole UtBot.

[alisevych]

Linked issue:

• Reduce IU plugin size #2141