ci: pin home crate to fix rust build (#4330)

Author: lrstewart

bindings/rust/generate/Cargo.toml

@@ -11,3 +11,4 @@ publish = false
 bindgen = "0.65"
 glob = "0.3"
 regex = "=1.9.6" # newer versions require rust 1.65, see https://github.com/aws/s2n-tls/issues/4242
+home = "=0.5.5" # newer versions require rust 1.70