Fix F#/C# versions for .NET 6/7

[mairaw]

We got a customer feedback for the site complaining about .NET 7 needing to support F# 7

It seems we decreased the version starting with 7.0.11

Fixes https://github.com/dotnet/website/issues/5834

[mairaw]

should this be 16.9 like the others?

[jaredpar]

yes nothing has changed with VB language versions.

[mairaw]

@jaredpar I realized I had added the wrong C# version for .NET 7 on my changes. So requesting a new review after my changes to make sure I didn't make other mistakes.

[Loboistaken]

This pull request updates the csharp-version and fsharp-version fields in the release-notes for versions 6.0 and 7.0. The most important changes include downgrading the csharp-version from 12.0 to 10.0 for version 6.0, and updating the csharp-version to 11.0 and the fsharp-version to 7.0 for version 7.0.

Changes to version 6.0:

• Updated csharp-version from 12.0 to 10.0 in multiple entries (release-notes/6.0/releases.json). [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]

Changes to version 7.0:

• Updated csharp-version from 12.0 to 11.0 and fsharp-version from 6.0 to 7.0 in multiple entries (release-notes/7.0/releases.json). [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]