(maint) Updates to run container tests on ruby 2.5.5

.travis.yml

@@ -21,6 +21,19 @@ matrix:
     - stage: r10k tests
       rvm: jruby
     - stage: r10k container tests
-      language: generic
+      language: ruby
+      rvm: 2.5.5
+      env:
+        - DOCKER_COMPOSE_VERSION=1.24.0
       script:
-        - cd docker && make lint && make build && make test
+        - |
+          set -ex
+          sudo rm /usr/local/bin/docker-compose
+          curl --location https://github.com/docker/compose/releases/download/${DOCKER_COMPOSE_VERSION}/docker-compose-`uname --kernel-name`-`uname --machine` > docker-compose 
+          chmod +x docker-compose
+          sudo mv docker-compose /usr/local/bin
+          cd docker
+          make lint
+          make build
+          make test
+          set +x

docker/Makefile

@@ -6,6 +6,10 @@ build_date := $(shell date -u +%FT%T)
 hadolint_available := $(shell hadolint --help > /dev/null 2>&1; echo $$?)
 hadolint_command := hadolint --ignore DL3008 --ignore DL3018 --ignore DL4000 --ignore DL4001
 hadolint_container := hadolint/hadolint:latest
+pwd := $(shell pwd)
+export BUNDLE_PATH = $(pwd)/.bundle/gems
+export BUNDLE_BIN = $(pwd)/.bundle/bin
+export GEMFILE = $(pwd)/Gemfile
 
 ifeq ($(IS_NIGHTLY),true)
 	dockerfile := Dockerfile.nightly
@@ -45,8 +49,10 @@ ifeq ($(IS_LATEST),true)
 endif
 
 test: prep
-	@bundle install --path .bundle/gems
-	@PUPPET_TEST_DOCKER_IMAGE=$(NAMESPACE)/r10k:$(version) bundle exec rspec r10k/spec
+	@bundle install --path $$BUNDLE_PATH --gemfile $$GEMFILE
+	@PUPPET_TEST_DOCKER_IMAGE=$(NAMESPACE)/r10k:$(version) \
+		bundle exec --gemfile $$GEMFILE \
+		rspec r10k/spec
 
 push-image: prep
 	@docker push $(NAMESPACE)/r10k:$(version)