Graduation Level Bug

[Schlaumeier5]

Changing the graduation level over the web interview (as admin), restarting the server and opening the student list results in the following server-side error:

java.lang.IllegalArgumentException: No such graduation level: 2025
        at de.igslandstuhl.database.api.GraduationLevel.of(GraduationLevel.java:42)
        at de.igslandstuhl.database.api.Student.fromSQL(Student.java:129)
        at de.igslandstuhl.database.server.Server.processSingleRequest(Server.java:115)
        at de.igslandstuhl.database.api.Student.get(Student.java:152)
        at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
        at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:575)
        at java.base/java.util.stream.AbstractPipeline.evaluateToArrayNode(AbstractPipeline.java:260)
        at java.base/java.util.stream.ReferencePipeline.toArray(ReferencePipeline.java:616)
        at java.base/java.util.stream.ReferencePipeline.toArray(ReferencePipeline.java:622)
        at java.base/java.util.stream.ReferencePipeline.toList(ReferencePipeline.java:627)
        at de.igslandstuhl.database.api.SchoolClass.getStudents(SchoolClass.java:160)
        at de.igslandstuhl.database.server.webserver.PostRequestHandler.lambda$registerHandlers$28(PostRequestHandler.java:287)
        at de.igslandstuhl.database.server.webserver.requests.HttpHandler.handleHttpRequest(HttpHandler.java:35)
        at de.igslandstuhl.database.server.webserver.PostRequestHandler.handlePostRequest(PostRequestHandler.java:83)
        at de.igslandstuhl.database.server.WebServer$ClientHandler.handlePost(WebServer.java:156)
        at de.igslandstuhl.database.server.WebServer$ClientHandler.run(WebServer.java:103)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
        at java.base/java.lang.Thread.run(Thread.java:840)

[Schlaumeier5]

This error can possibly lead to the student list not being displayed due to an HTTP 500 error