properly clear jump host from settings (fixes #2675)

terminus-ssh/src/components/editConnectionModal.component.pug

@@ -74,8 +74,8 @@
                     .header
                         .title Jump host
                     select.form-control([(ngModel)]='connection.jumpHost')
-                        option([value]='null') None
-                        option([value]='x.name', *ngFor='let x of config.store.ssh.connections') {{x.name}}
+                        option([ngValue]='null') None
+                        option([ngValue]='x.name', *ngFor='let x of config.store.ssh.connections') {{x.name}}
 
                 .form-line
                     .header