Let deployment-tools use the VMR commit hash (dotnet#42139)

Author: omajid

src/SourceBuild/content/repo-projects/deployment-tools.proj

@@ -9,10 +9,6 @@
     <RepositoryReference Include="source-build-reference-packages" />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(UseOfficialBuildVersioning)' != 'false'">
-    <EnvironmentVariables Include="LatestCommit=$(GitCommitHash)" />
-  </ItemGroup>
-
   <ItemGroup>
     <!-- https://github.com/dotnet/source-build/issues/4115. -->
     <EnvironmentVariables Include="PublishWindowsPdb=false" />