Update CODEOWNERS

Author: jimgrundy

CODEOWNERS

@@ -44,7 +44,7 @@
 
 /src/goto-analyzer/ @martin-cs @chris-ryder @peterschrammel
 /src/goto-harness/ @martin-cs @chris-ryder @peterschrammel
-/src/goto-instrument/ @martin-cs @chris-ryder @peterschrammel
+/src/goto-instrument/ @martin-cs @chris-ryder @peterschrammel @tautschnig @kroening
 /src/goto-instrument/contracts/ @tautschnig @feliperodri @remi-delmas-3000
 /doc/cprover-manual/contracts* @tautschnig @feliperodri @remi-delmas-3000
 /src/goto-diff/ @tautschnig @peterschrammel