Bump commons-net from 3.1 to 3.9.0

Bumps commons-net from 3.1 to 3.9.0.

---
updated-dependencies:
- dependency-name: commons-net:commons-net
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index cb92756..d3bbed9 100644
--- a/pom.xml
+++ b/pom.xml
@@ -323,7 +323,7 @@
     <dep.commons-httpclient.version>3.0.1</dep.commons-httpclient.version>
     <dep.commons-logging.version>1.1.1</dep.commons-logging.version>
     <dep.commons-io.version>2.1</dep.commons-io.version>
-    <dep.commons-net.version>3.1</dep.commons-net.version>
+    <dep.commons-net.version>3.9.0</dep.commons-net.version>
     <dep.commons-lang3.version>3.4</dep.commons-lang3.version>
     <dep.facebook-swift.version>0.14.0</dep.facebook-swift.version>
     <dep.fasterxml-jackson.version>2.10.0</dep.fasterxml-jackson.version>