Remove default values for Nix expression parameters

I'm not sure if this commit breaks everything in my monorepo. I think it
will.

Why am I doing this? Perhaps it's a bad idea. I don't fully understand how
readTree works. My ignorance is costing me hours of time spent debugging. In an
effort to better understand readTree, I'm removing the default values for my Nix
expression parameters, which I believe have preventing errors from surfacing.

1 files changed, 1 insertions, 1 deletions

diff --git a/mail/default.nix b/mail/default.nix
index d1b67b965626..a149ed8123bc 100644
--- a/mail/default.nix
+++ b/mail/default.nix
@@ -1,4 +1,4 @@
-{ depot ? import <depot> {}, ... }:
+{ depot, ... }:
 
 let
   inherit (builtins) fetchGit;