Fix issue related to flaky UI test with a remaining 'Update conflict' window

Error Message
The following shells remained open [Update conflict]
Stacktrace
java.lang.AssertionError: The following shells remained open [Update conflict]
Standard Output
13:34:36.882 ERROR [WorkbenchTestable][RequirementsRunner] Exception in test: testXMLFile no-configuration(org.jboss.tools.fuse.ui.bot.tests.CamelEditorTest)
Standard Error
org.eclipse.reddeer.common.exception.RedDeerException: Exception during sync execution in UI thread
	at org.eclipse.reddeer.common.util.Display.handleErrorOccured(Display.java:112)
	at org.eclipse.reddeer.common.util.Display.syncExec(Display.java:84)
	at org.eclipse.reddeer.core.handler.MenuHandler.getItems(MenuHandler.java:55)
	at org.eclipse.reddeer.core.lookup.MenuItemLookup.lookFor(MenuItemLookup.java:62)
	at org.eclipse.reddeer.swt.impl.menu.ContextMenuItem.<init>(ContextMenuItem.java:68)
	at org.eclipse.reddeer.swt.impl.menu.ContextMenuItem.<init>(ContextMenuItem.java:40)
	at org.jboss.tools.fuse.reddeer.utils.ProjectFactory.deleteAllProjects(ProjectFactory.java:146)
	at org.jboss.tools.fuse.ui.bot.tests.CamelEditorTest.setupDeleteProjects(CamelEditorTest.java:108)

Error Message
Exception during sync execution in UI thread
Stacktrace
org.eclipse.reddeer.common.exception.RedDeerException: Exception during sync execution in UI thread
	at org.jboss.tools.fuse.ui.bot.tests.CamelEditorTest.setupDeleteProjects(CamelEditorTest.java:108)
Caused by: java.lang.NullPointerException
Standard Output
13:34:36.880 ERROR [WorkbenchTestable][RequirementsRunner] Exception in test: testXMLFile no-configuration(org.jboss.tools.fuse.ui.bot.tests.CamelEditorTest)
Standard Error
org.eclipse.reddeer.core.exception.CoreLayerException: No matching widget found with Matcher matching when all matchers match: [Matcher matching widget with the same type as or type extending class org.eclipse.swt.custom.CTabItem, Matcher matching widgets with text that without mnenomic matches: is "Source"]
class org.eclipse.swt.widgets.Shell[shell: 'Update conflict'] with text 'Update conflict'
	class org.eclipse.swt.widgets.Label[shell: 'Update conflict'] with text ''
	class org.eclipse.swt.widgets.Label[shell: 'Update conflict'] with text 'The file 'cbr/src/main/resources/META-INF/spring/camel-context.xml' has been changed on the file system. Do you want to overwrite the changes made on the file system?'
	class org.eclipse.swt.widgets.Composite[shell: 'Update conflict'] with label 'The file 'cbr/src/main/resources/META-INF/spring/camel-context.xml' has been changed on the file system. Do you want to overwrite the changes made on the file system?'
		class org.eclipse.swt.widgets.Label[shell: 'Update conflict'] with label 'The file 'cbr/src/main/resources/META-INF/spring/camel-context.xml' has been changed on the file system. Do you want to overwrite the changes made on the file system?' with text ''
	class org.eclipse.swt.widgets.Composite[shell: 'Update conflict'] with label ''
		class org.eclipse.swt.widgets.Button[shell: 'Update conflict'] with label '' with text '&No'
		class org.eclipse.swt.widgets.Button[shell: 'Update conflict'] with label '' with text '&Yes'