Restore birch.2 references as comments

vagrant/release/devstack/Vagrantfile

@@ -66,6 +66,10 @@ openedx_releases = {
   "named-release/cypress" => {
     :name => "cypress-devstack", :file => "cypress-devstack.box",
   },
+  # Birch is deprecated and unsupported
+  # "named-release/birch.2" => {
+  #   :name => "birch-devstack-2", :file => "birch-2-devstack.box",
+  # },
 }
 openedx_releases.default = {
   :name => "cypress-devstack", :file => "cypress-devstack.box",

vagrant/release/fullstack/Vagrantfile

@@ -12,6 +12,10 @@ openedx_releases = {
   "named-release/cypress" => {
     :name => "cypress-fullstack", :file => "cypress-fullstack.box",
   },
+  # Birch is deprecated and unsupported
+  # "named-release/birch.2" => {
+  #   :name => "birch-fullstack-2", :file => "birch-2-fullstack.box",
+  # },
 }
 openedx_releases.default = {
   :name => "cypress-fullstack", :file => "cypress-fullstack.box",