nested exception is org.springframework.beans.FatalBeanException while loading plugin

Hi,

hope someone can help me here. I made a small plugin for teamcity. After some changes I started to getting an error during initialization of my plugin. Even though I reverted all changes, I still get this error and I have no idea where it comes from:

[2019-06-21 16:44:42,731]  ERROR - gins.spring.SpringPluginLoader - Error loading plugin 'lidofactory-plugin': Failed to initialize spring context: Unexpected exception parsing XML document from URL [jar:file:/Users/frankrudert/TeamCity/webapps/ROOT/WEB-INF/lib/common-impl.jar!/META-INF/per-plugin-shared-spring.xml]; nested exception is org.springframework.beans.FatalBeanException: Class [org.springframework.context.config.ContextNamespaceHandler] for namespace [http://www.springframework.org/schema/context] does not implement the [org.springframework.beans.factory.xml.NamespaceHandler] interface
org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from URL [jar:file:/Users/frankrudert/TeamCity/webapps/ROOT/WEB-INF/lib/common-impl.jar!/META-INF/per-plugin-shared-spring.xml]; nested exception is org.springframework.beans.FatalBeanException: Class [org.springframework.context.config.ContextNamespaceHandler] for namespace [http://www.springframework.org/schema/context] does not implement the [org.springframework.beans.factory.xml.NamespaceHandler] interface
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:414)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:336)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:181)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:217)
	at jetbrains.buildServer.plugins.spring.SpringPluginLoader$TeamCityPluginContext.doLoadBeanDefinitions(SpringPluginLoader.java:279)
	at jetbrains.buildServer.plugins.spring.SpringPluginLoader$TeamCityPluginContext.loadBeanDefinitions(SpringPluginLoader.java:265)
	at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:93)
	at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:129)
	at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:614)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:515)
	at jetbrains.buildServer.plugins.spring.SpringPluginLoader.pluginClassesLoaded(SpringPluginLoader.java:114)
	at sun.reflect.GeneratedMethodAccessor79.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at jetbrains.buildServer.util.EventDispatcher$3.run(EventDispatcher.java:128)
	at jetbrains.buildServer.util.NamedThreadFactory.executeWithNewThreadName(NamedThreadFactory.java:76)
	at jetbrains.buildServer.util.EventDispatcher.dispatch(EventDispatcher.java:122)
	at jetbrains.buildServer.util.EventDispatcher$2.invoke(EventDispatcher.java:72)
	at com.sun.proxy.$Proxy25.pluginClassesLoaded(Unknown Source)
	at jetbrains.buildServer.plugins.PluginManagerImpl$5.visitPlugin(PluginManagerImpl.java:417)
	at jetbrains.buildServer.plugins.PluginsCollection$1.run(PluginsCollection.java:97)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.springframework.beans.FatalBeanException: Class [org.springframework.context.config.ContextNamespaceHandler] for namespace [http://www.springframework.org/schema/context] does not implement the [org.springframework.beans.factory.xml.NamespaceHandler] interface
	at org.springframework.beans.factory.xml.DefaultNamespaceHandlerResolver.resolve(DefaultNamespaceHandlerResolver.java:128)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1405)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1400)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:172)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:142)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:94)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:508)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:392)
	... 26 more