Add property in MergedManifest.xml for .NET Core owned packages

[MilenaHristova]

As part of https://github.com/dotnet/release/issues/740 extend the MergedManifest packages and blobs models to include property DotNetReleaseShipping indicating that the assets will be published with the release infra.
DotNetReleaseShipping should be false by default and should only appear in MergedManifest.xml, it shouldn't get published to BAR

Release Note Category

• Feature changes/additions
• Bug fixes
• Internal Infrastructure Improvements

Release Note Description

Add DotNetReleaseShipping property to assets in MergedManifest.xml

[MilenaHristova]

This is in PR: #3311

I will merge it after the property gets to the asset manifests for all shipping repos ( after dotnet/arcade#14490 and https://github.com/dotnet/release/issues/822 are completed)

[MilenaHristova]

All PRs from https://github.com/dotnet/release/issues/822 on main are merged and repos have updated arcade so the new property is propagated to the asset manifest and we can make the change in MergedManifest.xml

[MilenaHristova]

This is done. We should see the property in merged manifest once Microsoft.DotNet.Maestro.Tasks version is updated in arcade and repos update arcade