Tighten up mvn and plugin versions

And add check during release.

Author: oschwald

dev-bin/release.sh

@@ -50,6 +50,7 @@ fi
 
 popd
 
+mvn versions:display-plugin-updates
 mvn versions:display-dependency-updates
 
 read -r -n 1 -p "Continue given above dependencies? (y/n) " should_continue

pom.xml

@@ -51,6 +51,26 @@
     </dependencies>
     <build>
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-enforcer-plugin</artifactId>
+                <version>3.4.1</version>
+                <executions>
+                  <execution>
+                    <id>enforce-maven</id>
+                    <goals>
+                      <goal>enforce</goal>
+                    </goals>
+                    <configuration>
+                      <rules>
+                        <requireMavenVersion>
+                          <version>3.2.5</version>
+                        </requireMavenVersion>
+                      </rules>
+                    </configuration>
+                  </execution>
+                </executions>
+            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-checkstyle-plugin</artifactId>