Minor cleanup of CommonManaged.props

Commit migrated from https://github.com/dotnet/core-setup/commit/b59facb5406186c02d622e3746396d3fcf83ac31

src/installer/managed/CommonManaged.props

@@ -6,14 +6,6 @@
   <Import Project="$(MSBuildThisFileDirectory)../../RepoDirectories.props" />
   <Import Project="$(RepoRoot)BranchInfo.props" />
 
-  <PropertyGroup>
-    <!-- BuildVersion Properties -->
-    <TodayTimeStamp>$([System.DateTime]::Now.ToString(yyyyMMdd))</TodayTimeStamp>
-    <BuildVersionFile Condition="'$(BuildVersionFile)'==''">$(ObjDir)BuildVersion-$(TodayTimeStamp).props</BuildVersionFile>
-  </PropertyGroup>
-
-  <Import Project="$(BuildVersionFile)" />
-
   <PropertyGroup>
     <VersionPrefix>$(MajorVersion).$(MinorVersion).$(PatchVersion)</VersionPrefix>
     <AssemblyFileVersion>$(VersionPrefix)</AssemblyFileVersion>
@@ -27,9 +19,20 @@
     <PackageThirdPartyNoticesFile>$(RepoRoot)THIRD-PARTY-NOTICES.TXT</PackageThirdPartyNoticesFile>
   </PropertyGroup>
 
+  <!--
+  Once https://github.com/dotnet/buildtools/issues/1548 is fixed, the following version sections should be simply
+  <Import Condition="Exists('$(ToolsDir)BuildVersion.targets')" Project="$(ToolsDir)BuildVersion.targets" />
+  -->
+  <PropertyGroup>
+    <TodayTimeStamp>$([System.DateTime]::Now.ToString(yyyyMMdd))</TodayTimeStamp>
+    <BuildVersionFile Condition="'$(BuildVersionFile)'==''">$(ObjDir)BuildVersion-$(TodayTimeStamp).props</BuildVersionFile>
+  </PropertyGroup>
+
+  <Import Condition="Exists('$(BuildVersionFile)')" Project="$(BuildVersionFile)" />
+
   <PropertyGroup Condition="'$(StabilizePackageVersion)' != 'true'">
     <!-- 
-    Ensure VersionSuffix is always set (especially during 'dotnet restore')
+    Ensure VersionSuffix is set (especially during 'dotnet restore')
     to work around https://github.com/NuGet/Home/issues/4337
      -->
     <VersionSuffix Condition="'$(PreReleaseLabel)' != ''">$(PreReleaseLabel)-</VersionSuffix>