treewide: apply linter suggestions

lib/keymap-helpers.nix

@@ -65,7 +65,7 @@ rec {
   # to ensure `lua` isn't evaluated when (e.g.) generating lua code.
   # Failure to do so will result in "option used but not defined" errors!
   deprecatedMapOptionSubmodule = mkMapOptionSubmodule { lua = true; };
-  removeDeprecatedMapAttrs = v: builtins.removeAttrs v [ "lua" ];
+  removeDeprecatedMapAttrs = v: removeAttrs v [ "lua" ];
 
   mkModeOption =
     default:

lib/plugins/utils.nix

@@ -138,7 +138,7 @@
         };
       in
       lib.pipe depsToEnable [
-        (builtins.map enableDepConditionally)
+        (map enableDepConditionally)
         lib.listToAttrs
       ];
   };

lib/types.nix

@@ -140,7 +140,6 @@ rec {
   pluginLuaConfig = types.submodule (
     { config, ... }:
     let
-      inherit (builtins) toString;
       inherit (lib.nixvim.utils) mkBeforeSection mkAfterSection;
     in
     {

lib/utils.internal.nix

@@ -138,7 +138,7 @@ rec {
         message = "${prefix} ${lib.trim a.message}";
       };
     in
-    builtins.map processAssertion (lib.toList assertions);
+    map processAssertion (lib.toList assertions);
 
   /**
     Convert one or several conditional warnings to a final warning list.