Packages need to stabilize for shipping .NET 7

[ViktorHofer]

1. Product dependencies in the Versions.props files must not be prerelease. Fixed with Bump main version to RC1 #72068 and Make 'RC' lowercase in versions.props #72110
2. Product dependencies in the Versions.props files must be on the latest patch version for libraries dependencies. Product dependencies in Versions.props must be on the latest patch version for libraries dependencies #73871
3. We must be using the compiler from the SDK and unpin the compiler if it's pinned. Unpin C# compiler version for repo #65317
4. The Intellisense package must be up-to-date before we release. @carlossanlop will take care of this gradually until the RC2 snap.

cc @dotnet/runtime-infrastructure

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Issue Details

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• Product dependencies in the Versions.props files must not be prerelease.
• Product dependencies in the Versions.props files must be on the latest patch version for libraries dependencies, i.e. System.Memory.
• We must be using the compiler from the SDK and unpin the compiler if it's pinned.
• The Intellisense package must be up-to-date before we release.

cc @dotnet/runtime-infrastructure

Author:	ViktorHofer
Assignees:	-
Labels:	blocking-release, area-Infrastructure
Milestone:	7.0.0

[jeffschwMSFT]

@carlossanlop can you take a look at this issue?

[carlossanlop]

I'll sync with @ViktorHofer tomorrow on this.

[carlossanlop]

I already took care of item no. 1: #72068 and #72110

I will take care of item no. 4 gradually until we snap RC2.

Pending clarifying 2 and 3.

Edit: We have an issue tracking no. 3. Viktor provided this summary:

The work involves just removing this one property: https://github.com/dotnet/runtime/blob/main/eng/Versions.props#L23. But we can't do until we have an sdk with the right compiler (presumably RC1 will be the right time to depend on its compiler).

Also for no. 2:

this involves updating the versions listed here to the latest available version on nuget: https://github.com/dotnet/runtime/blob/main/eng/Versions.props#L90-L120
these versions aren't flowing. These are actual nuget dependencies. So manually looking up the latest version on nuget.org
It must be done before we ship 7.0.0, as close as possible to the release ideally. But we could also do it once now.

Instructions:

1. Go to https://www.nuget.org/
2. Search for nuget package name. For example, Microsoft.Bcl.AsyncInterfaces
3. Check the latest stable version of the package, in this case 6.0.0.
4. If the version is newer than what's in Versions.props, update it.
   We should ignore: StyleCopAnalyzersVersion, SystemTextJsonVersion, runtimenativeSystemIOPortsVersion

[carlossanlop]

Item no. 2 has been merged to main. Here is the backport to release/7.0-rc1: #74024

[carlossanlop]

For item no. 3, @jkoritzinsky wrote in #65317 (comment) :

This wasn't able to be fixed in #72145 because of a regression in Roslyn. We'll fix this before we release (likely after RC1).