Stop enabling all engines

Previously we installed all engines regardless of if they were specified
in the config. This just about worked, but had the downside of
installing extensions regardless of if the engine was enabled. By
filtering the engines before adding them we can prevent this

Change-Id: Id135f2905fc09fab140cd0484398793900bc11bb
Reviewed-on: https://git.clicks.codes/c/Chimera/NixFiles/+/505
Tested-by: Skyler Grey <minion@clicks.codes>
Reviewed-by: Samuel Shuert <coded@clicks.codes>
diff --git a/modules/home/browser/firefox/search/default.nix b/modules/home/browser/firefox/search/default.nix
index d02aa70..40faf1f 100644
--- a/modules/home/browser/firefox/search/default.nix
+++ b/modules/home/browser/firefox/search/default.nix
@@ -186,6 +186,7 @@
         "Wikipedia (en)"
       ];
       calculated = lib.pipe engineData [
+        (lib.filterAttrs (engine: _: builtins.elem engine config.chimera.browser.firefox.search.engines))
         (builtins.mapAttrs (
           name: value: {
             engines.${name} =