Python runner stderr fix for crashlog()

[S4adam]

What?
A custom, simple class to write to 2 stderr channels (explained down below).

Why?
Currently, Python runner does not produce errors to Crashlog(), but only and only to si inst stderr, so the aim is to capture and redirect errors from stderr to both the process's stderr and the Instance's stderr endpoint (so that they are shown in both crashlog and inst stderr).

Usage:
You need to build, and use a custom runner-py docker image:

1. Clone this pr:D

2. docker build --pull --rm -f "packages/python-runner/Dockerfile" -t runner:v1 "./"

3. yarn start:dev --runner-py-image=runner:v1

4. Deploy any Python Sequence that produces an exception, example Sequence: crash-py.tar.gz.
   si seq deploy crash-py.tar.gz

5. Verify that you can see the Exception message both in Transform Hub's Crashlog and Instance's stderr (as shown below):
   

Review checks:

These aspects need to be checked by the reviewer:

• Verify and confirm operation (please post a screenshot)
• All STH tests pass
• All Scramjet Cloud Platform tests pass
• Documentation is updated or no changes

https://app.clickup.com/t/24308805/VDM-993