Extension resolution does not work for nested hugr

[hsemenenko]

check_hugr is not able to resolve extensions for hugr which has lower_funcs hugr. Example in this Guppy PR: CQCL/guppylang#1091.

Error message:

E       selene_hugr_qis_compiler.HugrReadError: Error loading HUGR package.
E       
E       Caused by:
E           ModelImport { source: ImportError { inner: ExtensionResolution(MissingOpExtension { node: Some(Node(8)), op: "OpaqueOp:tket.quantum.H", missing_extension: IdentList("tket.quantum"), available_extensions: [IdentList("arithmetic.conversions"), IdentList("arithmetic.float"), IdentList("arithmetic.float.types"), IdentList("arithmetic.int"), IdentList("arithmetic.int.types"), IdentList("collections.array"), IdentList("collections.borrow_arr"), IdentList("collections.list"), IdentList("collections.static_array"), IdentList("collections.value_array"), IdentList("logic"), IdentList("prelude"), IdentList("ptr")] }), generator: Some("guppylang (guppylang-internals-v0.22.0)-v0.21.2") } } at line 1 column 34319