update ohsome parent to 2.4

Jenkinsfile

@@ -157,11 +157,10 @@ pipeline {
           }
 
           // warnings plugin
-          rtMaven.run pom: 'pom.xml', goals: '--batch-mode -V -e compile checkstyle:checkstyle pmd:pmd pmd:cpd findbugs:findbugs com.github.spotbugs:spotbugs-maven-plugin:3.1.7:spotbugs -Dmaven.repo.local=.m2'
+          rtMaven.run pom: 'pom.xml', goals: '--batch-mode -V -e compile checkstyle:checkstyle pmd:pmd pmd:cpd com.github.spotbugs:spotbugs-maven-plugin:3.1.7:spotbugs -Dmaven.repo.local=.m2'
 
           recordIssues enabledForFailure: true, tools: [mavenConsole(),  java(), javaDoc()]
           recordIssues enabledForFailure: true, tool: checkStyle()
-          recordIssues enabledForFailure: true, tool: findBugs()
           recordIssues enabledForFailure: true, tool: spotBugs()
           recordIssues enabledForFailure: true, tool: cpd(pattern: '**/target/cpd.xml')
           recordIssues enabledForFailure: true, tool: pmdParser(pattern: '**/target/pmd.xml')

pom.xml

@@ -11,7 +11,7 @@
     <parent>
         <groupId>org.heigit.ohsome</groupId>
         <artifactId>ohsome-parent</artifactId>
-        <version>2.3</version>
+        <version>2.4</version>
     </parent>
 
     <dependencies>