Bump guava from 28.0-jre to 28.1-jre

Bumps [guava](https://github.com/google/guava) from 28.0-jre to 28.1-jre.
- [Release notes](https://github.com/google/guava/releases)
- [Commits](https://github.com/google/guava/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

pom.xml

@@ -63,7 +63,7 @@
     <license>apache_v2</license>
     <debug>false</debug>
     <java.level>1.6</java.level>
-    <guava.version>28.0-jre</guava.version>
+    <guava.version>28.1-jre</guava.version>
     <assertj-core.version>3.12.2</assertj-core.version>
     <commons-io.version>2.6</commons-io.version>
   </properties>