Minimize the set of tokio features that need to be enabled.

Author: matts1

watchman/rust/watchman_client/Cargo.toml

@@ -17,8 +17,16 @@ maplit = "1.0"
 serde = { version = "1.0.126", features = ["derive", "rc"] }
 serde_bser = { version = "0.4", path = "../serde_bser" }
 thiserror = "1.0"
-tokio = { version = "1.7.1", features = ["full", "test-util"] }
-tokio-util = { version = "0.6", features = ["full"] }
+tokio = {
+  version = "1.7.1",
+  features = [
+    "io-util",
+    "net",
+    "process",
+    "test-util"
+  ]
+}
+tokio-util = { version = "0.6", features = ["codec"] }
 
 [target.'cfg(windows)'.dependencies]
 winapi = { version = "0.3", features = ["fileapi", "handleapi", "winbase", "winuser"] }