More finely scoped github actions and kubernetes_test build docker images

[costrouc]

Closes #1084

This PR has a few goals:

• Make it so that only the tests that need to run actually run for CI given commits
• build the docker images for each kubernetes test

[costrouc]

Going to merge since this only affects the CI and makes all our other tests more reliable.

[costrouc]

This also allows for easier local testing. Here is how you can run local tests

export QHUB_GH_BRANCH=qhub-test

mkdir mydeployment
pushd mydeployment

minikube start --driver=docker
eval $(minikube docker-env)

python ../tests/scripts/minikube-loadbalancer-ip.py
minikube addons enable metallb

qhub render --config qhub-config.yaml

pushd image
TAG=qhub-test docker buildx bake
popd

qhub deploy --config qhub-config.yaml