erpnext: plaid: enable currency conversions support

This pulls in change 661 (Id5b54d34a19b76d03a47d7c5a43d04bbe8f956db) of
the Clicks ERPNext Fork:
- https://git.clicks.codes/c/Clicks/Forks/ERPNext/+/661

That change attempts to add currency conversions when a transaction is
made in a currency which is not your account's home currency. It was
decided that as we have no test data beyond accounts which are on our
main instance, this needs to go up for us to properly test it, so it is
currently up.

Change-Id: Ib7398a73a0402d852d518f4046d7776bd18422a3
Reviewed-on: https://git.clicks.codes/c/Infra/NixFiles/+/666
Reviewed-by: Samuel Shuert <coded@clicks.codes>
Tested-by: Samuel Shuert <coded@clicks.codes>
diff --git a/modules/common/frappe.nix b/modules/common/frappe.nix
index f6128f9..b26d606 100644
--- a/modules/common/frappe.nix
+++ b/modules/common/frappe.nix
@@ -6,7 +6,17 @@
     package = pkgs.frappix.frappe;
 
     apps = [
-      pkgs.frappix.erpnext
+      (pkgs.frappix.erpnext.overrideAttrs (oldAttrs: {
+        src = pkgs.mkAssets (pkgs.frappix.appSources.wiki // {
+          src = builtins.fetchTree {
+            type = "git";
+            url = "https://git.clicks.codes/Clicks/Forks/ERPNext";
+            narHash = "sha256-epjhNJugFQTTdoR6Ac0qD+pntCDmiS+spZV6XIt+60M=";
+            rev = "f07bbd8cbb744c0b3ab85b47c1f0bc42a9265f9d";
+            shallow = true;
+          };
+        });
+      }))
       pkgs.frappix.wiki
     ];