Enable step to run stack tests on Windows (#2173)

Enable windows step to run stack tests and update the test script.
The test script now adds commands to test at least the stack up (with
some failures) and the stack down process.

.buildkite/pipeline.yml

@@ -74,21 +74,19 @@ steps:
       - step: unit-tests-linux
         allow_failure: false
 
-  # Disable step due to docker errors: https://buildkite.com/elastic/elastic-package/builds/4023#0191ff3a-f18b-4e43-9219-4957da065c37/1827-1829
-  # Related issue: https://github.com/elastic/elastic-package/issues/2107 
-  # - label: ":windows: Run stack tests"
-  #   key: stack-tests-windows
-  #   command: ".buildkite/scripts/stack_tests_windows.ps1"
-  #   agents:
-  #     provider: "gcp"
-  #     image: "${WINDOWS_AGENT_IMAGE}"
-  #   depends_on:
-  #     - step: check-static
-  #       allow_failure: false
-  #     - step: unit-tests-windows
-  #       allow_failure: false
-  #   artifact_paths:
-  #     - 'C:\ProgramData\chocolatey\logs\chocolatey.log'
+  - label: ":windows: Run stack tests"
+    key: stack-tests-windows
+    command: ".buildkite/scripts/stack_tests_windows.ps1"
+    agents:
+      provider: "gcp"
+      image: "${WINDOWS_AGENT_IMAGE}"
+    depends_on:
+      - step: check-static
+        allow_failure: false
+      - step: unit-tests-windows
+        allow_failure: false
+    artifact_paths:
+      - 'C:\ProgramData\chocolatey\logs\chocolatey.log'
 
   - wait: ~
     continue_on_failure: true

.buildkite/scripts/stack_tests_windows.ps1

@@ -30,7 +30,7 @@ function withDocker($version) {
 
 function withDockerCompose($version) {
     Write-Host "-- Install Docker Compose $version --"
-    choco install -y docker-compose --version $version
+    choco install -y docker-compose --allow-downgrade --version $version
     setupChocolateyPath
 }
 
@@ -56,9 +56,18 @@ go mod download -x
 echo "--- Running stack tests"
 $ErrorActionPreference = "Continue" # set +e
 
-# TODO: stack status checks that we can call docker-compose, but we should try a stack up.
+# TODO: stack status checks that we can call docker, but we should try a stack up to try also with docker-compose with a full scenario.
 # stack up doesn't work because we didn't manage to enable the linux engine, and we don't have Windows native images.
-go run . stack status
+echo "Stack Status"
+go run . stack status -v
+echo "Stack up"
+# running this stack up command adds the required files under ~/.elastic-package to run afterwards "elastic-package stack down" successfully
+# that uses docker-compose under the hood
+go run . stack up -v -d
+echo "Stack Status"
+go run . stack status -v
+echo "Stack down"
+go run . stack down -v
 
 $EXITCODE=$LASTEXITCODE
 $ErrorActionPreference = "Stop"