Currently, each test suite spins up its own kind cluster, which results
in longer e2e test times as each test suite needs to wait for the
cluster to be ready and for images to download. This commit creates two
new virtual test suites that are run before and after the actual e2e
tests and are responsible for creating and destroying a kind cluster
respectively. Any test suite that needs a fresh cluster can still spin
up its own using the `create_cluster` helper in the lib.sh file.
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>