Add back roll forward to rzls (#10530)

Fixes https://devdiv.visualstudio.com/DevDiv/_workitems/edit/2088486

Seems this was inadvertently removed in
#10453

@ryzngard I'm pretty out of my depth here about what is required, but a
local build of rzls with this change does fix the problem. Are there any
other project properties that might be important, that I should bring
back?

src/Razor/src/rzls/rzls.csproj

@@ -8,7 +8,7 @@
     <RootNamespace>Microsoft.AspNetCore.Razor.LanguageServer</RootNamespace>
     <EnableApiCheck>false</EnableApiCheck>
     <IsShippingPackage>true</IsShippingPackage>
-
+    <RollForward>LatestMajor</RollForward>
     <!--
         Build a nuget package for this project.  This is not consumed as a standard NuGet package; it just
     contains