Selecting existing directory as a settings.xml target fails the installation.

reproduce
- make sure that settings.xml file doesn't exist on tested location
- choose to install quickstarts from Configure runtime environment options
- choose to Specify an alternate path to the Maven settings.xml file
- use non-existing file in existing directory first (e.g. /home/pkremens/setting.xml)
- Warning dialogue about settings.xml creation should appear, press Cancel
- remove settings.xml from the path (e.g. /home/pkremens)

actual
IOExcetpion during installation - source file exists but is a directory

expected
Installer should offer same warning dialogue as in case before (see 6.4.0 installer)