I want to update Magnolia to 5.2 but in the installation process i've got following error:

info.magnolia.module.delta.TaskExecutionException: Could not bootstrap: Can't find resource to bootstrap at /mgnl-bootstrap/resources/pages/config.modules.resources.pages.xml
at info.magnolia.module.delta.BootstrapResourcesTask.execute(BootstrapResourcesTask.java:69)
at info.magnolia.module.ModuleManagerImpl.applyDeltas(ModuleManagerImpl.java:512)
at info.magnolia.module.ModuleManagerImpl.installOrUpdateModule(ModuleManagerImpl.java:494)
at info.magnolia.module.ModuleManagerImpl$1.doExec(ModuleManagerImpl.java:277)
at info.magnolia.context.MgnlContext$VoidOp.exec(MgnlContext.java:415)
at info.magnolia.context.MgnlContext$VoidOp.exec(MgnlContext.java:412)
at info.magnolia.context.MgnlContext.doInSystemContext(MgnlContext.java:386)
at info.magnolia.module.ModuleManagerImpl.performInstallOrUpdate(ModuleManagerImpl.java:271)
at info.magnolia.module.ui.ModuleManagerWebUI$2.run(ModuleManagerWebUI.java:127)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.io.IOException: Can't find resource to bootstrap at /mgnl-bootstrap/resources/pages/config.modules.resources.pages.xml
at info.magnolia.importexport.BootstrapUtil.bootstrap(BootstrapUtil.java:86)
at info.magnolia.module.delta.BootstrapResourcesTask.execute(BootstrapResourcesTask.java:67)
... 9 more