don't declare the same dependency twice

pom.xml

@@ -63,9 +63,5 @@
       <groupId>fr.soleil.lib.comete</groupId>
       <artifactId>TangoDataSource</artifactId>
     </dependency>
-    <dependency>
-      <groupId>ch.qos.logback</groupId>
-      <artifactId>logback-classic</artifactId>
-    </dependency>
   </dependencies>
 </project>
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