Update plugin parent POM to latest (#216)

pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>org.jenkins-ci.plugins</groupId>
     <artifactId>plugin</artifactId>
-    <version>4.87</version>
+    <version>5.1</version>
     <relativePath />
   </parent>
 
@@ -28,17 +28,14 @@
     <revision>4.11.0</revision>
     <changelist>999999-SNAPSHOT</changelist>
     <gitHubRepo>jenkinsci/${project.artifactId}-plugin</gitHubRepo>
-    <jenkins.version>2.475</jenkins.version>
+    <jenkins.version>2.479</jenkins.version>
     <no-test-jar>false</no-test-jar>
     <!-- 
       beware https://github.com/jenkinsci/plugin-pom/issues/705 and https://github.com/jenkinsci/plugin-pom/issues/707
       if updating these ensure the used transitive deps that have their version managed are updated as direct dependencies and any unused ones are removed.
     -->
     <okio.version>3.5.0</okio.version>
     <kotlin.version>1.9.22</kotlin.version>
-    <!-- TODO JENKINS-73339 until in parent POM -->
-    <jenkins-test-harness.version>2265.v3da_49c8134d6</jenkins-test-harness.version>
-    <maven.compiler.release>17</maven.compiler.release>
   </properties>
 
   <dependencyManagement>
@@ -64,12 +61,6 @@
         <scope>import</scope>
         <type>pom</type>
       </dependency>
-      <!-- TODO JENKINS-73339 until in parent POM, work around https://github.com/jenkinsci/plugin-pom/issues/936 -->
-      <dependency>
-        <groupId>jakarta.servlet</groupId>
-        <artifactId>jakarta.servlet-api</artifactId>
-        <version>5.0.0</version>
-      </dependency>
     </dependencies>
   </dependencyManagement>