Bump MetaGraphs.jl compat

Author: simsurace

Project.toml

@@ -15,7 +15,7 @@ Graphs = "1.4.1"
 InteractiveUtils = "1"
 JLD2 = "0.1.11, 0.2, 0.3, 0.4, 0.5, 0.6"
 JuliaFormatter = "1"
-MetaGraphs = "0.7"
+MetaGraphs = "0.7, 0.8"
 SimpleTraits = "0.9"
 Test = "1"
 julia = "1.6"