[MSITE-861] remove obsolete dependency (#29)

* remove obsolete dependency
diff --git a/pom.xml b/pom.xml
index bd72020..1f6c845 100644
--- a/pom.xml
+++ b/pom.xml
@@ -214,19 +214,6 @@
   </properties>
 
   <dependencies>
-    <!-- exclude obsolete runtime artifact included by transitive dependencies (pulled by doxia-site-renderer) -->
-    <dependency>
-      <groupId>commons-logging</groupId>
-      <artifactId>commons-logging</artifactId>
-      <version>1.1</version>
-      <exclusions>
-        <exclusion>
-          <groupId>javax.servlet</groupId>
-          <artifactId>servlet-api</artifactId>
-        </exclusion>
-      </exclusions>
-    </dependency>
-
     <dependency>
       <groupId>org.apache.maven.reporting</groupId>
       <artifactId>maven-reporting-api</artifactId>