Use Python edenfsctl for eden clone

Summary:
Switch eden_clone to use the Python edenfsctl (via EdenCmdType::Python /
legacy_command config key) for the clone subprocess.
This skips the overhead of launching rust cli and falling back to python cli.

Reviewed By: janezhang10, genevievehelsel

Differential Revision: D99192225

fbshipit-source-id: c71e1ab6d83d10de80f08445ebd2917e5c9a0dcd

Author: vilatto

eden/integration/hg/lib/hg_extension_test_base.py

@@ -202,6 +202,8 @@ def hg_clone_additional_repo(
             "--config",
             f"edenfs.command={cmd}",
             "--config",
+            f"edenfs.legacy_command={cmd}",
+            "--config",
             f"edenfs.basepath={self.eden._base_dir}",
             *clone_args,
             cwd=self.mounts_dir,

eden/scm/lib/clone/src/lib.rs

@@ -157,7 +157,11 @@ pub fn eden_clone(
 ) -> Result<()> {
     let config = repo.config();
 
-    let mut clone_command = edenfs_client::build_eden_command(config)?;
+    // We don't have `clone` supported in rust edenfs cli for now. Specifying
+    // python cli to avoid the overhead of falling back.
+    // We should remove this hack once `clone` is supported in rust.
+    let mut clone_command =
+        edenfs_client::build_eden_command_type(config, edenfs_client::EdenCmdType::Python)?;
 
     clone_command.args([
         OsStr::new("clone"),

eden/scm/sapling/testing/ext/edenfs.py

@@ -34,6 +34,7 @@ def testsetup(t: TestTmp):
         sl_config.write(f"""
 [edenfs]
 command={edenfsctl_path}
+legacy_command={edenfsctl_path}
 backing-repos-dir=$TESTTMP/.eden-backing-repos
 
 [clone]