Bump ITensors compat to fix directsum issue (#79)

Author: mtfishman

Project.toml

@@ -19,7 +19,7 @@ SplitApplyCombine = "03a91e81-4c3e-53e1-a0a4-9c0c8f19dd66"
 [compat]
 Compat = "3, 4"
 HDF5 = "0.15, 0.16"
-ITensors = "0.3.18"
+ITensors = "0.3.48"
 Infinities = "0.1"
 IterTools = "1"
 KrylovKit = "0.5, 0.6"