Add frappe wiki

Continuing on from our ERPNext patch, frappe wiki is another bit of
software we'd like. In particular, we want to use it to document various
tools for non-infra members who may not be aware of them.

We have made an upstream package in
https://github.com/blaggacao/frappix/pull/2, so this should now be
out-of-the-box

Change-Id: I12a03347aa25304077e6502894c933c62e435d05
Reviewed-on: https://git.clicks.codes/c/Infra/NixFiles/+/536
Reviewed-by: Samuel Shuert <coded@clicks.codes>
Tested-by: Skyler Grey <minion@clicks.codes>
diff --git a/modules/common/frappe.nix b/modules/common/frappe.nix
index 8479aff..9720364 100644
--- a/modules/common/frappe.nix
+++ b/modules/common/frappe.nix
@@ -7,6 +7,7 @@
 
     apps = [
       pkgs.frappix.erpnext
+      pkgs.frappix.wiki
     ];
 
     sites."frappe.clicks.codes" = {
@@ -16,6 +17,7 @@
 
       apps = [
         "frappe"
+        "wiki"
         "erpnext"
       ];
     };