Retire in-active governance repos

As discussed in TC meeting[1], let's retire the
in-active governance repos mentioned in below etherpad:

- https://etherpad.opendev.org/p/governance-repos-cleanup

Depends-On: https://review.opendev.org/c/openstack/project-config/+/797778/1
Depends-On: https://review.opendev.org/c/openstack/project-config/+/797747

[1] https://meetings.opendev.org/meetings/tc/2021/tc.2021-06-17-15.00.log.html#l-98

Change-Id: I20c909018a2197e4d8c940e48e934682b14ea8f5

reference/legacy.yaml

@@ -289,6 +289,42 @@ fuel:
       repos:
         - openstack/python-fuelclient
 
+Governance:
+  irc-channel: openstack-tc
+  url: https://governance.openstack.org/tc/
+  partial: yes
+  deliverables:
+    arch-wg:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/arch-wg
+    openstack-specs:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/openstack-specs
+    project-navigator-data:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/project-navigator-data
+    Enterprise Working Group:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/enterprise-wg
+        - openstack/workload-ref-archs
+    Ops Tags Team:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/ops-tags-team
+    Scientific Working Group:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/scientific-wg
+    User Committee:
+      retired-on: 2021-06-23
+      repos:
+        - openstack/governance-uc
+        - openstack/uc-recognition
+
 horizon:
   irc-channel: openstack-horizon
   service: Dashboard

reference/technical-committee-repos.yaml

@@ -1,14 +1,11 @@
 ---
 # List of repositories owned by the technical committee
 Technical Committee:
-  - repo: openstack/arch-wg
   - repo: openstack/election
   - repo: openstack/goal-tools
   - repo: openstack/governance
   - repo: openstack/governance-website
   - repo: openstack/ideas
   - repo: openstack/openstack
-  - repo: openstack/openstack-specs
-  - repo: openstack/project-navigator-data
   - repo: openstack/project-team-guide
   - repo: openstack/service-types-authority

reference/user-committee-repos.yaml

@@ -1,12 +0,0 @@
----
-# List of repositories owned by the User Committee and subcommittees
-Enterprise Working Group:
-  - repo: openstack/enterprise-wg
-  - repo: openstack/workload-ref-archs
-Ops Tags Team:
-  - repo: openstack/ops-tags-team
-Scientific Working Group:
-  - repo: openstack/scientific-wg
-User Committee:
-  - repo: openstack/governance-uc
-  - repo: openstack/uc-recognition