[dotnet] update changelog for 4.5
+v4.5.0
+======
+* Add CDP support for v105, and remove v102
+* Update Select class to error when elements are disabled
+* Add support for installing unsigned add-ons in Firefox
+* Add return value for installing add-ons in Firefox
+
v4.4.0
======
* Add CDP support for v104, and remove v101
