Rich hover invalid images mess with dimensions

[Tyriar]

Testing #127372

Using statusbar-sample with:

(myStatusBarItem as any).tooltip2 = new vscode.MarkdownString('Testing **the** new _tooltip_! Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_!Testing **the** new _tooltip_![Testing **the** new _tooltip_!](https://github.com)Testing **the** new _tooltip_!');

The hover shows fine then the invalid image loads in:

It works fine when the image loads in properly: