[27.1 backport] fix: container stream should not be terminated by ctx

[Benehiko]

• backports: fix: container stream should not be terminated by ctx #5247
• fixes: SIGTERM sent to docker run command doesn't send a SIGTERM to the main process running inside the container anymore. #5241

- What I did
Prevent the hijacked stream from exiting on main ctx cancellation. When the user sends a termination signal to the CLI while attached to a container, the signal should be forwarded to the container and handled by the process inside the container. The CLI should wait for the container to gracefully exit.

If the user wishes to exit without waiting, sending more termination requests will still forcefully exit the CLI.

- How I did it

- How to verify it

handle_sigterm.sh

#!/bin/sh

# Function to handle SIGTERM
handle_sigterm() {
    echo "Received SIGTERM, exiting..."
    exit 0
}

trap 'handle_sigterm' TERM

while true; do
    echo "Waiting for sigterm"
    sleep 10
done

⋊> ~/G/cli on hotfix-sigterm-container ◦ build/docker run -i \                                                    
                                                      -v $HOME/Downloads/:/home:ro \
                                                      alpine:latest \
                                                      /home/handle_sigterm.sh
Waiting for sigterm
Waiting for sigterm
Received SIGTERM, exiting...

⋊> ~ ps -ef | grep "handle_sigterm.sh" | grep "docker run"
benehiko  279458  277233  1 17:48 pts/5    00:00:00 build/docker run -i -v /home/benehiko/Downloads/:/home:ro alpine:latest /home/handle_sigterm.sh
⋊> ~ kill -15 279458 

- Description for the changelog

sending a termination request to the CLI while attached to a container, will wait for the container to exit before closing the stream.

- A picture of a cute animal (not mandatory but encouraged)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 61.42%. Comparing base (52848fb) to head (333103d).

Additional details and impacted files

@@           Coverage Diff           @@
##             27.0    #5250   +/-   ##
=======================================
  Coverage   61.42%   61.42%           
=======================================
  Files         298      298           
  Lines       20815    20816    +1     
=======================================
+ Hits        12785    12786    +1     
+ Misses       7117     7114    -3     
- Partials      913      916    +3