base: do not use required fields on currency

We have a rule "Do Not Test Required In Field View Form"

bt5/erp5_base/SkinTemplateItem/portal_skins/erp5_base/Currency_viewFieldLibrary/my_reference.xml

@@ -10,10 +10,9 @@
             <key> <string>delegated_list</string> </key>
             <value>
               <list>
-                <string>title</string>
                 <string>description</string>
                 <string>external_validator</string>
-                <string>required</string>
+                <string>title</string>
               </list>
             </value>
         </item>
@@ -100,10 +99,6 @@
                     <key> <string>form_id</string> </key>
                     <value> <string>Base_viewFieldLibrary</string> </value>
                 </item>
-                <item>
-                    <key> <string>required</string> </key>
-                    <value> <int>1</int> </value>
-                </item>
                 <item>
                     <key> <string>target</string> </key>
                     <value> <string>Click to edit the target</string> </value>

bt5/erp5_base/SkinTemplateItem/portal_skins/erp5_base/Currency_viewFieldLibrary/my_title.xml

@@ -10,9 +10,8 @@
             <key> <string>delegated_list</string> </key>
             <value>
               <list>
-                <string>title</string>
                 <string>description</string>
-                <string>required</string>
+                <string>title</string>
               </list>
             </value>
         </item>
@@ -85,10 +84,6 @@
                     <key> <string>form_id</string> </key>
                     <value> <string>Base_viewFieldLibrary</string> </value>
                 </item>
-                <item>
-                    <key> <string>required</string> </key>
-                    <value> <int>1</int> </value>
-                </item>
                 <item>
                     <key> <string>target</string> </key>
                     <value> <string>Click to edit the target</string> </value>