feat(base): autoload bash env for other shells

[axonasif]

Description

This adds startup scripts specific to fish and zsh to autoload the bash environment variables within their sessions without altering the user configuration (i.e. dotfiles)

Related Issue(s)

Fixes gitpod-io/gitpod#10105

How to test

Open this PR on Gitpod.

Build and run:

cd base
docker build -t base . && docker run -it base

We will land in a bash shell. Now we can create a script inside ~/.bashrc.d from the bash session and then switch to another shell to test if it picked it up.

echo 'export TESTVAR=hello' > ~/.bashrc.d/testing

# Switch to fish
fish

# Check the variable
echo $TESTVAR

# Exit
exit

# Switch to zsh
zsh

# Check
echo $TESTVAR

# Exit
exit

# We'll be back on `bash` (however, it didn't pick up `~/.bashrc.d/testing`, because it was created during the session)
echo $TESTVAR # will be empty
# let's check in `env` as well
env | grep TESTVAR # will be empty

# Now let's reload bash session
exec bash -l

# Now it should be available on bash as well
env | grep TESTVAR

Release Notes

Documentation

[axonasif]

This could be implemented via supervisor as well, we just need to write two files, that could be helpful if someone is using a non-gitpod image.

[gitpod-io]

[axonasif]

Converted to draft.
Context here.