Release v0.7

[amis92]

• [x] Changelog update
• [x] Update version.json
• [x] AzP release to nuget.org
• [x] Changelog update with version number and date
• [x] GitHub release
• [x] Switch milestones

[amis92]

Release published: https://github.com/AArnott/CodeGeneration.Roslyn/releases/tag/v0.7.63