pom.xml: upgrade kemitix-checkstyle-ruleset to 2.1.2

Includes checkstyle 7.5.1, so remove custom configuration.

README.md

@@ -28,7 +28,7 @@ maven-javadoc-plugin.version|2.10.4
 maven-source-plugin.version|3.0.1
 maven-gpg-plugin.version|1.6
 maven-deploy-plugin.version|2.8.2
-kemitix-checkstyle-ruleset.version|2.0.4
+kemitix-checkstyle-ruleset.version|2.1.2
 digraph-dependency.version|0.7.0
 maven-compiler-plugin.version|3.6.0
 maven-surefire-plugin.version|2.19.1
@@ -49,7 +49,8 @@ The Checkstyle plugin is configured using the
 `kemitix-checkstyle-ruleset-maven-plugin`.
 
 The `kemitix-checkstyle-ruleset` provides five levels of checks. The
-default is set to `5-complexity`, the most strict.
+default is set to `5-complexity`, the most strict. It runs during the
+`validate` phase.
 
 ### Configuration
 

pom.xml

@@ -41,7 +41,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <kemitix.build.directory>target</kemitix.build.directory>
-        <kemitix-checkstyle-ruleset.version>2.0.4</kemitix-checkstyle-ruleset.version>
+        <kemitix-checkstyle-ruleset.version>2.1.2</kemitix-checkstyle-ruleset.version>
         <kemitix-checkstyle-ruleset.level>5-complexity</kemitix-checkstyle-ruleset.level>
 
         <lombok.version>1.16.12</lombok.version>
@@ -187,9 +187,6 @@
                 <groupId>net.kemitix</groupId>
                 <artifactId>kemitix-checkstyle-ruleset-maven-plugin</artifactId>
                 <version>${kemitix-checkstyle-ruleset.version}</version>
-                <configuration>
-                    <checkstyleVersion>7.4</checkstyleVersion>
-                </configuration>
                 <executions>
                     <execution>
                         <phase>validate</phase>