test: Add GCP Run Test

This commit adds the GCP test that formerly ran in LinuxKitCI to run
under rtf.

As GitHub Actions doesn't currently support adding secret files, I've
skipped this test for now. Credentials can be passed via environment
variable but as RTF runs with `-x` the contents is viewable in the logs.

I will create an issue to follow up and find either a way of writing the
variable to file that doesn't compromise it. Or perhaps another approach
that is more compatible with GH actions

Signed-off-by: Dave Tucker <dave@dtucker.co.uk>

test/cases/010_platforms/110_gcp/000_run/test.sh

@@ -0,0 +1,40 @@
+#!/bin/sh
+# SUMMARY: Check that gcp image boots in gcp
+# LABELS: skip
+
+set -e
+
+# Source libraries. Uncomment if needed/defined
+#. "${RT_LIB}"
+. "${RT_PROJECT_ROOT}/_lib/lib.sh"
+
+NAME=gcp-$(cat /dev/urandom | tr -dc 'a-z0-9' | fold -w 8 | head -n 1)
+export CLOUDSDK_CORE_PROJECT="moby-datakit-ci"
+export CLOUDSDK_COMPUTE_ZONE="europe-west1-d"
+export CLOUDSDK_IMAGE_BUCKET="linuxkit-gcp-test-bucket"
+
+clean_up() {
+	rm -rf ${NAME}*
+    docker run -i --rm \
+        -e CLOUDSDK_CORE_PROJECT \
+        -v `pwd`/certs:/certs \
+        google/cloud-sdk \
+        sh -c "gcloud auth activate-service-account --key-file /certs/svc_account.json; \
+        gsutil rm gs://${CLOUDSDK_IMAGE_BUCKET}/${NAME}.img.tar.gz" || true
+    rm -rf certs
+}
+trap clean_up EXIT
+
+[ -n "$GCLOUD_CREDENTIALS" ] || exit 1
+mkdir -p certs
+printf '%s' "$GCLOUD_CREDENTIALS" > certs/svc_account.json
+
+linuxkit build -format gcp -name "${NAME}" test.yml
+[ -f "${NAME}.img.tar.gz" ] || exit 1
+linuxkit push gcp -keys certs/svc_account.json -bucket linuxkit-gcp-test-bucket ${NAME}.img.tar.gz
+# tee output of lk run to file as grep hides failures and doesn't 
+# always allow the vm to be cleaned up
+linuxkit run gcp -keys certs/svc_account.json ${NAME} | tee ${NAME}.log
+grep -q "Welcome to LinuxKit" ${NAME}.log
+
+exit 0

test/cases/010_platforms/110_gcp/000_run/test.yml

@@ -0,0 +1,13 @@
+kernel:
+  image: linuxkit/kernel:4.19.76
+  cmdline: "console=ttyS0"
+init:
+  - linuxkit/init:1d8e0532ca588c5ad0d9ca6038349a70bb7ac626
+  - linuxkit/runc:c1f0db27e71d948f3134b31ce76276f843849b0a
+onboot:
+  - name: poweroff
+    image: linuxkit/poweroff:b498d30dd9660090565537fceb9e757618737a85
+    command: ["/bin/sh", "/poweroff.sh", "10"]
+trust:
+  org:
+    - linuxkit