CompatHelper: add new compat entry for Compat at version 4, (keep existing compat) (#876)

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

Author: github-actions[bot]

Project.toml

@@ -7,6 +7,7 @@ InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
 OrderedCollections = "bac558e1-5e72-5ebc-8fee-abe8a469f55d"
 
 [compat]
+Compat = "4"
 OrderedCollections = "1.1.0"
 julia = "1.6"