Add syntax highlighting for Ampersand nodes (#13737)

GitOrigin-RevId: 39c81ecb765adc4b33244b5f0f1eab81594dcba1

services/web/frontend/js/features/source-editor/languages/latex/latex-language.ts

@@ -166,6 +166,7 @@ export const LaTeXLanguage = LRLanguage.define({
         MathDelimiter: t.literal,
         DoubleDollar: t.keyword,
         Tilde: t.keyword,
+        Ampersand: t.keyword,
         Comment: t.comment,
         'UsePackage/OptionalArgument/ShortOptionalArg/Normal': t.attributeValue,
         'UsePackage/ShortTextArgument/ShortArg/Normal': t.tagName,