fix: export ABI type (#73)

Author: sabotagebeats

src/ape/types/__init__.py

@@ -1,7 +1,8 @@
-from .contract import Bytecode, Checksum, Compiler, ContractType, Source
+from .contract import ABI, Bytecode, Checksum, Compiler, ContractType, Source
 from .manifest import PackageManifest, PackageMeta
 
 __all__ = [
+    "ABI",
     "Bytecode",
     "Checksum",
     "Compiler",