treewide: remove redundant quotes

nixos/modules/programs/less.nix

@@ -54,8 +54,8 @@ in
         type = types.attrsOf types.str;
         default = {};
         example = {
-          "h" = "noaction 5\e(";
-          "l" = "noaction 5\e)";
+          h = "noaction 5\e(";
+          l = "noaction 5\e)";
         };
         description = "Defines new command keys.";
       };
@@ -74,7 +74,7 @@ in
         type = types.attrsOf types.str;
         default = {};
         example = {
-          "\e" = "abort";
+          e = "abort";
         };
         description = "Defines new line-editing keys.";
       };
@@ -111,11 +111,11 @@ in
     environment.systemPackages = [ pkgs.less ];
 
     environment.variables = {
-      "LESSKEY_SYSTEM" = toString lessKey;
+      LESSKEY_SYSTEM = toString lessKey;
     } // optionalAttrs (cfg.lessopen != null) {
-      "LESSOPEN" = cfg.lessopen;
+      LESSOPEN = cfg.lessopen;
     } // optionalAttrs (cfg.lessclose != null) {
-      "LESSCLOSE" = cfg.lessclose;
+      LESSCLOSE = cfg.lessclose;
     };
 
     warnings = optional (