add a test to ensure the file is not written to when the version does not change
add a test to ensure the file is not written to when the version does not change

wrozmiarek/msbuildtasks,jricke/msbuildtasks,AArnott/msbuildtasks,loresoft/msbuildtasks,smallkid/msbuildtasks,stimpy77/msbuildtasks,arekbee/msbuildtasks