update Cargo.toml

Author: rob-p

crates/sshash-py/Cargo.toml

@@ -10,4 +10,4 @@ crate-type = ["cdylib"]
 
 [dependencies]
 sshash-lib = { path = "../sshash-lib" }
-pyo3 = { version = "0.28.2", features = ["extension-module"] }
+pyo3 = { version = "0.28.2", features = ["extension-module", "abi3-py38"] }