fix(test): Remove bbdb-notmuch.el from the bbdb source files

bbdb package fails to compile because it doesn't have notmuch as a dependency.
bbdb itself isn't specific to notmuch and shouldn't depend on the library, so
I will exclude bbdb-notmuch.el from bbdb.

test/twist.nix

@@ -44,6 +44,7 @@ emacsTwist {
   inputOverrides = {
     bbdb = _: super: {
       files = builtins.removeAttrs super.files [
+        "bbdb-notmuch.el"
         "bbdb-vm.el"
         "bbdb-vm-aux.el"
       ];