Avoid eagerly getting "full" commit details for inline blame

[eamodio]

Description

Unless we are in a Live Share, we avoid adding a hover to the inline blame decoration, and instead relay on the on-demand hover provider. But we are still loading the full commit details eagerly for no real reason.

[eamodio]

While this fix, avoids the eager loading for the inline blame specifically, we will still end up eagerly loading the full commit details if the status bar blame is also enabled. As VS Code doesn't provide a way to delay load status bar hovers. See microsoft/vscode#145096 (though the VS Code team closed it)