A deleteDir() step in pipeline for a project with non-ASCII filenames does
the stack trace below, only seen in classic Web-GUI (BlueOcean just sees the
job as failed with no indication of details); replacing by "rm -rf dirname/"
is a functional but not so portable workaround:

java.nio.file.InvalidPathException: Malformed input or input contains unmappable characters: /tmp/jenkins/workspace/hub_fty-alert-engine_master-IJUIAC5NJ7QYYFY3UV32XFKXMSWZ2KLYWNCXG5I4CLBYLZ2IBCIQ/tmp/test-check-withDRAFT/src/selftest-rw/realpower.default@��lu��ou��k�� K����.rule
	at sun.nio.fs.UnixPath.encode(UnixPath.java:147)
	at sun.nio.fs.UnixPath.<init>(UnixPath.java:71)
	at sun.nio.fs.UnixFileSystem.getPath(UnixFileSystem.java:281)
	at java.io.File.toPath(File.java:2234)
	at hudson.Util.isSymlink(Util.java:508)
Also:   hudson.remoting.Channel$CallSiteStackTrace: Remote call to jenkins2-agent-13
		at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1693)
		at hudson.remoting.UserResponse.retrieve(UserRequest.java:310)
		at hudson.remoting.Channel.call(Channel.java:908)
		at hudson.FilePath.act(FilePath.java:986)
		at hudson.FilePath.act(FilePath.java:975)
		at hudson.FilePath.deleteRecursive(FilePath.java:1177)
		at org.jenkinsci.plugins.workflow.steps.DeleteDirStep$Execution.run(DeleteDirStep.java:77)
		at org.jenkinsci.plugins.workflow.steps.DeleteDirStep$Execution.run(DeleteDirStep.java:69)
		at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution$1$1.call(SynchronousNonBlockingStepExecution.java:49)
		at hudson.security.ACL.impersonate(ACL.java:260)
		at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution$1.run(SynchronousNonBlockingStepExecution.java:46)
		at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
		at java.util.concurrent.FutureTask.run(FutureTask.java:266)
		at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
		at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
		at java.lang.Thread.run(Thread.java:745)
Caused: java.io.IOException
	at hudson.Util.isSymlink(Util.java:522)
	at hudson.FilePath.deleteRecursive(FilePath.java:1200)
	at hudson.FilePath.deleteContentsRecursive(FilePath.java:1219)
	at hudson.FilePath.deleteRecursive(FilePath.java:1201)
	at hudson.FilePath.deleteContentsRecursive(FilePath.java:1219)
	at hudson.FilePath.deleteRecursive(FilePath.java:1201)
	at hudson.FilePath.deleteContentsRecursive(FilePath.java:1219)
	at hudson.FilePath.deleteRecursive(FilePath.java:1201)
	at hudson.FilePath.access$1000(FilePath.java:196)
	at hudson.FilePath$14.invoke(FilePath.java:1180)
	at hudson.FilePath$14.invoke(FilePath.java:1177)
	at hudson.FilePath$FileCallableWrapper.call(FilePath.java:2760)
	at hudson.remoting.UserRequest.perform(UserRequest.java:207)
	at hudson.remoting.UserRequest.perform(UserRequest.java:53)
	at hudson.remoting.Request$2.run(Request.java:358)
	at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:748)
Caused: java.io.IOException: remote file operation failed: /tmp/jenkins/workspace/hub_fty-alert-engine_master-IJUIAC5NJ7QYYFY3UV32XFKXMSWZ2KLYWNCXG5I4CLBYLZ2IBCIQ/tmp/test-check-withDRAFT at hudson.remoting.Channel@63a18f51:jenkins2-agent-13
	at hudson.FilePath.act(FilePath.java:993)
	at hudson.FilePath.act(FilePath.java:975)
	at hudson.FilePath.deleteRecursive(FilePath.java:1177)
	at org.jenkinsci.plugins.workflow.steps.DeleteDirStep$Execution.run(DeleteDirStep.java:77)
	at org.jenkinsci.plugins.workflow.steps.DeleteDirStep$Execution.run(DeleteDirStep.java:69)
	at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution$1$1.call(SynchronousNonBlockingStepExecution.java:49)
	at hudson.security.ACL.impersonate(ACL.java:260)
	at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution$1.run(SynchronousNonBlockingStepExecution.java:46)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Finished: FAILURE