MULE-6831: Applications deleted when deployment fails

_  Cleaning tests
(cherry picked from commit d4134cb)
MULE-6831: Applications deleted when deployment fails

_  Fixing flaky test
(cherry picked from commit 4070c95)
MULE-6831: Applications deleted when deployment fails

_  Fixing flaky test: all test should add applications using the synchronized utility methods
(cherry picked from commit 12cd91f)
MULE-6831: Applications deleted when deployment fails

_  Fixing flaky tests: AppDirWatcher#run can be executed twice before mockito verifies the interaction with the mock. This flaky test was a really caused by a bug. Fixed decoding zombie file' urls
(cherry picked from commit 5fcc340)
MULE-6831: Applications deleted when deployment fails

_ Fixing flaky test: org.mule.module.launcher.DeploymentServiceTestCase#deploysInvalidExplodedAppAfterStartup by synchronizing access to applications in MuleDeploymentService#stop
(cherry picked from commit cc61a02)