[mistral] Create yoga branch for client and non-client libs

This creates the stable/yoga branch for all client and non-client
libraries now that we are past the lib freeze on February 24th.

If the team wants to wait for a specific patch to make it to the
library, someone from the team can -1 the patch to have it held, or
update that patch with a different commit SHA.

Patches with no response will be merged by Friday, March 4th.

Change-Id: I758d6204822b6c1732a66fe8d35fa06dbff41421

deliverables/yoga/mistral-extra.yaml

@@ -11,3 +11,6 @@ releases:
     projects:
       - repo: openstack/mistral-extra
         hash: face48a2d65a28733e55279f933ea18c5fd13867
+branches:
+  - name: stable/yoga
+    location: 11.2.0

deliverables/yoga/mistral-lib.yaml

@@ -11,3 +11,6 @@ releases:
     projects:
       - repo: openstack/mistral-lib
         hash: 44c33f2ccd8b059f68db59114c71ba95dfae574d
+branches:
+  - name: stable/yoga
+    location: 2.6.0

deliverables/yoga/python-mistralclient.yaml

@@ -11,3 +11,6 @@ releases:
     projects:
       - repo: openstack/python-mistralclient
         hash: 608ec45cef72d822d1242e0aefcea7d044662adc
+branches:
+  - name: stable/yoga
+    location: 4.4.0