Remove default BuildInParallel attributes (#65378)

Cleanup: Remove BuildInParallel=false attributes which are the default setting.

Author: ViktorHofer

eng/Subsets.props

@@ -269,7 +269,7 @@
 
   <ItemGroup Condition="$(_subset.Contains('+clr.packages+')) and '$(PgoInstrument)' != 'true'">
     <ProjectToBuild Include="$(CoreClrProjectRoot).nuget\coreclr-packages.proj" Pack="true" Category="clr" />
-    <ProjectToBuild Include="$(CoreClrProjectRoot)tools\dotnet-pgo\dotnet-pgo-pack.proj" Pack="true" BuildInParallel="false" Category="clr" Condition="'$(DotNetBuildFromSource)' != 'true' and '$(RuntimeFlavor)' != 'Mono'"/>
+    <ProjectToBuild Include="$(CoreClrProjectRoot)tools\dotnet-pgo\dotnet-pgo-pack.proj" Pack="true" Category="clr" Condition="'$(DotNetBuildFromSource)' != 'true' and '$(RuntimeFlavor)' != 'Mono'"/>
   </ItemGroup>
 
   <ItemGroup Condition="$(_subset.Contains('+clr.nativeaotlibs+')) and '$(NativeAotSupported)' == 'true'">
@@ -303,7 +303,7 @@
 
   <!-- Host sets -->
   <ItemGroup Condition="$(_subset.Contains('+host.native+'))">
-    <CorehostProjectToBuild Include="$(SharedNativeRoot)corehost\corehost.proj" SignPhase="Binaries" BuildInParallel="false" />
+    <CorehostProjectToBuild Include="$(SharedNativeRoot)corehost\corehost.proj" SignPhase="Binaries" />
     <ProjectToBuild Include="@(CorehostProjectToBuild)" Pack="true" Category="host" />
   </ItemGroup>
 
@@ -313,7 +313,7 @@
   </ItemGroup>
 
   <ItemGroup Condition="$(_subset.Contains('+host.pkg+')) and '$(PgoInstrument)' != 'true'">
-    <PkgprojProjectToBuild Include="$(InstallerProjectRoot)pkg\projects\host-packages.proj" SignPhase="MsiFiles" BuildInParallel="false" />
+    <PkgprojProjectToBuild Include="$(InstallerProjectRoot)pkg\projects\host-packages.proj" SignPhase="MsiFiles" />
     <ProjectToBuild Include="@(PkgprojProjectToBuild)" Pack="true" Category="host" />
   </ItemGroup>
 
@@ -390,12 +390,12 @@
   </ItemGroup>
 
   <ItemGroup Condition="$(_subset.Contains('+publish+'))">
-    <ProjectToBuild Include="$(InstallerProjectRoot)prepare-artifacts.proj" Pack="true" BuildInParallel="false" Category="publish" />
+    <ProjectToBuild Include="$(InstallerProjectRoot)prepare-artifacts.proj" Pack="true" Category="publish" />
   </ItemGroup>
 
   <!-- Utility -->
   <ItemGroup Condition="$(_subset.Contains('+regeneratedownloadtable+'))">
-    <ProjectToBuild Include="$(RepositoryEngineeringDir)regenerate-download-table.proj" Pack="true" BuildInParallel="false" />
+    <ProjectToBuild Include="$(RepositoryEngineeringDir)regenerate-download-table.proj" Pack="true" />
   </ItemGroup>
 
   <!-- Set default configurations. -->