Bump maven-javadoc-plugin from 3.1.0 to 3.1.1 (#993)

Bumps [maven-javadoc-plugin](https://github.com/apache/maven-javadoc-plugin) from 3.1.0 to 3.1.1.
- [Commits](apache/maven-javadoc-plugin@maven-javadoc-plugin-3.1.0...maven-javadoc-plugin-3.1.1)

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

Author: dependabot-preview[bot]

exonum-java-binding/pom.xml

@@ -417,7 +417,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-javadoc-plugin</artifactId>
-          <version>3.1.0</version>
+          <version>3.1.1</version>
           <configuration>
             <source>${java.compiler.source}</source>
             <doclint>none</doclint>

exonum-light-client/pom.xml

@@ -235,7 +235,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
-        <version>3.1.0</version>
+        <version>3.1.1</version>
         <configuration>
           <source>${java.compiler.source}</source>
           <doclint>none</doclint>