Add Release Note (feature): Comes with [Git Credential Manager v2.6.0](https://github.com/git-ecosystem/git-credential-manager/releases/tag/v2.6.0).

Add Release Note (feature): Comes with [Git Credential Manager v2.6.0](https://github.com/git-ecosystem/git-credential-manager/releases/tag/v2.6.0). #145