upgrade scala-maven-plugin to 4.1.0 (apache#6469)

### Motivation
The Pulsar examples include some third-party libraries with security vulnerabilities.
- log4j-core-2.8.1
https://www.cvedetails.com/cve/CVE-2017-5645

### Modifications

- Upgraded the version of scala-maven-plugin from 4.0.1 to 4.1.0. log4j-core-2.8.1 were installed because scala-maven-plugin depends on it.

examples/flink/pom.xml

@@ -133,7 +133,7 @@
       <plugin>
         <groupId>net.alchim31.maven</groupId>
         <artifactId>scala-maven-plugin</artifactId>
-        <version>4.0.1</version>
+        <version>4.1.0</version>
         <executions>
           <execution>
             <goals>

examples/spark/pom.xml

@@ -116,7 +116,7 @@
       <plugin>
         <groupId>net.alchim31.maven</groupId>
         <artifactId>scala-maven-plugin</artifactId>
-        <version>4.0.1</version>
+        <version>4.1.0</version>
         <executions>
           <execution>
             <goals>