Revert "Revert "Change Windows Containers to Windows Server Nano (#5488…

…)" (#5589)"

This reverts commit ae82727.

.gitlab-ci.yml

@@ -2706,7 +2706,7 @@ docker_build_agent7_windows1809:
     IMAGE: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-agent/agent
     BUILD_CONTEXT: Dockerfiles/agent
     TAG_SUFFIX: -7
-    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:windowsservercore-1809 --build-arg WITH_JMX=false
+    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:nanoserver-1809 --build-arg WITH_JMX=false
   script:
     - $ErrorActionPreference = "Stop"
     - $SHORT_CI_COMMIT_SHA = ${CI_COMMIT_SHA}.Substring(0,7)
@@ -2732,7 +2732,7 @@ docker_build_agent7_windows1809_jmx:
     IMAGE: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-agent/agent
     BUILD_CONTEXT: Dockerfiles/agent
     TAG_SUFFIX: -7-jmx
-    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:windowsservercore-1809 --build-arg WITH_JMX=true
+    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:nanoserver-1809 --build-arg WITH_JMX=true
   script:
     - $ErrorActionPreference = "Stop"
     - $SHORT_CI_COMMIT_SHA = ${CI_COMMIT_SHA}.Substring(0,7)
@@ -2759,7 +2759,7 @@ docker_build_agent7_windows1909:
     IMAGE: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-agent/agent
     BUILD_CONTEXT: Dockerfiles/agent
     TAG_SUFFIX: -7
-    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:windowsservercore-1909 --build-arg WITH_JMX=false
+    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:nanoserver-1909 --build-arg WITH_JMX=false
   script:
     - $ErrorActionPreference = "Stop"
     - $SHORT_CI_COMMIT_SHA = ${CI_COMMIT_SHA}.Substring(0,7)
@@ -2785,7 +2785,7 @@ docker_build_agent7_windows1909_jmx:
     IMAGE: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-agent/agent
     BUILD_CONTEXT: Dockerfiles/agent
     TAG_SUFFIX: -7-jmx
-    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:windowsservercore-1909 --build-arg WITH_JMX=true
+    BUILD_ARG: --build-arg BASE_IMAGE=mcr.microsoft.com/powershell:nanoserver-1909 --build-arg WITH_JMX=true
   script:
     - $ErrorActionPreference = "Stop"
     - $SHORT_CI_COMMIT_SHA = ${CI_COMMIT_SHA}.Substring(0,7)

releasenotes/notes/containerized-windows-nano-7e6157fcbe75ea7f.yaml

@@ -0,0 +1,11 @@
+# Each section from every releasenote are combined when the
+# CHANGELOG.rst is rendered. So the text needs to be worded so that
+# it does not depend on any information only available in another
+# section. This may mean repeating some details, but each section
+# must be readable independently of the other.
+#
+# Each section note must be formatted as reStructuredText.
+---
+enhancements:
+  - |
+    Windows Docker image is now based on Windows Server Nano instead of Windows Server Core.