[winstackers] Transition Train to EM

This transition the train branch to extended maintenance.
Changes for bugfixes and things the team deems important are
still encouraged, but there will no longer be official releases
off of the branch.

Please +1 if the team is ready for us to proceed with this
transition, or -1 if there are any final backports currently in
flight that we should wait for. For the latter case, please
update the patch with the new commit hash after doing a final
release to get those changes out so we know to proceed with the
transition.

Change-Id: I7d758952a09a399a9644760979f2b975469e327b

deliverables/train/compute-hyperv.yaml

@@ -23,6 +23,10 @@ releases:
     projects:
       - repo: openstack/compute-hyperv
         hash: 2070a6c798a3eeea32de2751f4088e460f2e0f6a
+  - version: train-em
+    projects:
+      - repo: openstack/compute-hyperv
+        hash: 2070a6c798a3eeea32de2751f4088e460f2e0f6a
 branches:
   - name: stable/train
     location: 9.0.0.0rc1

deliverables/train/networking-hyperv.yaml

@@ -15,6 +15,10 @@ releases:
       - hash: 537e9aeb7841f810e49cd157295468441ecda981
         repo: openstack/networking-hyperv
     version: 7.3.1
+  - version: train-em
+    projects:
+      - repo: openstack/networking-hyperv
+        hash: 537e9aeb7841f810e49cd157295468441ecda981
 branches:
   - location: 7.3.0
     name: stable/train

deliverables/train/os-win.yaml

@@ -23,6 +23,10 @@ releases:
     projects:
       - repo: openstack/os-win
         hash: 3bdedd9f38eab5e94b2d1761d35773d9b88fbd7d
+  - version: train-em
+    projects:
+      - repo: openstack/os-win
+        hash: 3bdedd9f38eab5e94b2d1761d35773d9b88fbd7d
 branches:
   - location: 4.3.1
     name: stable/train