slapos_category: Include "Subscription" allocation scope

This category, when set on a computer, defines is as Open for Allocation, but only Subscribers can allocate. Normally, only instances that are linked to a Subscription Request.

master/bt5/slapos_category/PathTemplateItem/portal_categories/allocation_scope/open/subscription.xml

+<?xml version="1.0"?>
+<ZopeData>
+  <record id="1" aka="AAAAAAAAAAE=">
+    <pickle>
+      <global name="Category" module="erp5.portal_type"/>
+    </pickle>
+    <pickle>
+      <dictionary>
+        <item>
+            <key> <string>_Add_portal_content_Permission</string> </key>
+            <value>
+              <tuple>
+                <string>Assignor</string>
+                <string>Manager</string>
+              </tuple>
+            </value>
+        </item>
+        <item>
+            <key> <string>_Add_portal_folders_Permission</string> </key>
+            <value>
+              <tuple>
+                <string>Assignor</string>
+                <string>Manager</string>
+              </tuple>
+            </value>
+        </item>
+        <item>
+            <key> <string>_Copy_or_Move_Permission</string> </key>
+            <value>
+              <tuple>
+                <string>Assignor</string>
+                <string>Manager</string>
+              </tuple>
+            </value>
+        </item>
+        <item>
+            <key> <string>_Delete_objects_Permission</string> </key>
+            <value>
+              <tuple>
+                <string>Assignor</string>
+                <string>Manager</string>
+              </tuple>
+            </value>
+        </item>
+        <item>
+            <key> <string>_Modify_portal_content_Permission</string> </key>
+            <value>
+              <tuple>
+                <string>Assignee</string>
+                <string>Assignor</string>
+                <string>Manager</string>
+                <string>Owner</string>
+              </tuple>
+            </value>
+        </item>
+        <item>
+            <key> <string>categories</string> </key>
+            <value>
+              <tuple/>
+            </value>
+        </item>
+        <item>
+            <key> <string>description</string> </key>
+            <value> <string>Allocate services to anyone</string> </value>
+        </item>
+        <item>
+            <key> <string>effective_date</string> </key>
+            <value>
+              <none/>
+            </value>
+        </item>
+        <item>
+            <key> <string>id</string> </key>
+            <value> <string>subscription</string> </value>
+        </item>
+        <item>
+            <key> <string>portal_type</string> </key>
+            <value> <string>Category</string> </value>
+        </item>
+        <item>
+            <key> <string>title</string> </key>
+            <value> <string>Subscription</string> </value>
+        </item>
+      </dictionary>
+    </pickle>
+  </record>
+</ZopeData>