sourceInfo does not have revCount with flake-compat, differing from getFlake

[charles-dyfis-net]

Using Nix 2.8.1, a flake from git has the attributes rev, shortRev, revCount, lastModified and lastModifiedDate all under flake.sourceInfo.

However, with flake-compat, flake.sourceInfo has rev, shortRev, lastModified and lastModifiedDate, but not revCount directly under flake.sourceInfo.

revCount is available under flake.sourceInfo.outPath in this scenario.