It it possible to override the detected Cake version using the CakeContribGuidelinesOverrideTargetFrameworkCakeVersion setting:
(Keep in mind, though, that it is not recommended override the detected version.)
<PropertyGroup>
<CakeContribGuidelinesOverrideTargetFrameworkCakeVersion>2.0.0</CakeContribGuidelinesOverrideTargetFrameworkCakeVersion>
</PropertyGroup>