Remove usage of Groovy macros in AWM pages

If a user with PR edits these pages, the groovy macro will cease to work and thus AWM will be broken. Same if an admin user upgrades a subwiki for which there are changes to these pages requiring PR.

Affected pages:

• https://github.com/xwiki/xwiki-platform/blob/bb06bc1e03b6ff47f40bd4ae54e67b4c28e935c6/xwiki-platform-core/xwiki-platform-appwithinminutes/xwiki-platform-appwithinminutes-ui/src/main/resources/AppWithinMinutes/ClassEditSheet.xml#L41-L41
• https://github.com/xwiki/xwiki-platform/blob/bb06bc1e03b6ff47f40bd4ae54e67b4c28e935c6/xwiki-platform-core/xwiki-platform-appwithinminutes/xwiki-platform-appwithinminutes-ui/src/main/resources/AppWithinMinutes/DynamicMessageTool.xml#L39-L39