CompatHelper: bump compat for Compat to 4, (keep existing compat) (#136)

Co-authored-by: CompatHelper Julia <[email protected]>

Author: github-actions[bot]

Project.toml

@@ -17,7 +17,7 @@ Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 
 [compat]
 ArnoldiMethod = "0.1, 0.2"
-Compat = "3.40"
+Compat = "3.40, 4"
 DataStructures = "0.17, 0.18"
 Inflate = "0.1.2"
 SimpleTraits = "0.9"