app-admin/aws-rds-tools: Remove useless maintainer <description/>

Remove useless/redundant maintainer <description/>. It does not benefit
bug wrangling, and only wastes developer's time on reading it. Few tips:

- assignee/CC is implied by ordering, there is no reason to repeat it,
- we know that maintainer is maintainer (la la la la la),
- most of adjectives for maintainer are of no value and/or are obvious.

app-admin/aws-rds-tools/metadata.xml

@@ -4,9 +4,8 @@
   <maintainer type="person">
     <email>[email protected]</email>
     <name>Sergey Zhuga</name>
-    <description>Proxied maintainer; set to assignee in all bugs</description>
   </maintainer>
-<maintainer type="project">
+  <maintainer type="project">
     <email>[email protected]</email>
     <name>Proxy Maintainers</name>
   </maintainer>