add pepsi upload --prepare flag

tools/pepsi/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pepsi"
-version = "7.34.0"
+version = "7.35.0"
 edition.workspace = true
 license.workspace = true
 homepage.workspace = true

tools/pepsi/src/upload.rs

@@ -42,8 +42,11 @@ pub struct UploadArguments {
     /// Skip the OS version check
     #[arg(long)]
     pub skip_os_check: bool,
+    /// Build, don't upload
+    #[arg(long)]
+    pub prepare: bool,
     /// The Robots to upload to e.g. 20w or 10.1.24.22
-    #[arg(required = true)]
+    #[arg(required_unless_present("prepare"))]
     pub robots: Vec<RobotAddress>,
 }
 
@@ -138,6 +141,10 @@ pub async fn upload(arguments: Arguments, repository: &Repository) -> Result<()>
             .wrap_err("failed to build")?;
     }
 
+    if arguments.upload.prepare {
+        return Ok(());
+    }
+
     repository
         .populate_upload_directory(&upload_directory, &[hulk_binary])
         .await