Move "Open as preview" button so that it's in the same spot as "Reopen as source file"

[branets-dasha]

The "Open as Preview" button in markdown files and the "Reopen as source file" button in the previews are in different spots. Switching back and forth between source and preview requires mouse movements. It would be great if those two buttons stayed in the same spot.

Switching the positions of the "Open as Preview" and "Open Preview to the Side" buttons would probably solve the issue.

In source mode:

In preview mode: