Switch hack to use the new envtest tool

We can now drop the `setup-envtest.sh` script, and instead just use
`source <(setup-envtest fetch -k ${version} -p env)` (plus a couple
lines to install setup-envtest ;-)).

hack/check-everything.sh

@@ -20,16 +20,28 @@ set -o pipefail
 
 hack_dir=$(dirname ${BASH_SOURCE})
 source ${hack_dir}/common.sh
-source ${hack_dir}/setup-envtest.sh
 
 tmp_root=/tmp
 kb_root_dir=$tmp_root/kubebuilder
 
 ENVTEST_K8S_VERSION=${ENVTEST_K8S_VERSION:-"1.19.2"}
 
-fetch_envtest_tools "$kb_root_dir"
-fetch_envtest_tools "${hack_dir}/../pkg/internal/testing/integration/assets"
-setup_envtest_env "$kb_root_dir"
+# set up envtest tools if necessary
+if [[ -z "${KUBEBUILDER_ASSETS:-""}" ]]; then
+    header_text "installing envtest tools@${ENVTEST_K8S_VERSION} with setup-envtest"
+    # install this in a subshell to avoid messing with the cwd
+    tmp_bin=/tmp/cr-tests-bin
+    (
+        # don't presume to install for the user
+        cd ${hack_dir}/../tools/setup-envtest
+        GOBIN=${tmp_bin} go install .
+    )
+    source <(${tmp_bin}/setup-envtest fetch -k ${ENVTEST_K8S_VERSION} -p env)
+fi
+# link the assets into integration
+for tool in kube-apiserver etcd kubectl; do
+    ln -f -s "${KUBEBUILDER_ASSETS:?unable find envtest assets}/${tool}" "${hack_dir}/../pkg/internal/testing/integration/assets/bin/${tool}"
+done
 
 ${hack_dir}/verify.sh
 ${hack_dir}/test-all.sh