C++: Fixed enum class class names (#2342)

The `class` keyword in `enum class` enums was falsely highlighted as the class name.

components/prism-cpp.js

@@ -1,6 +1,6 @@
 Prism.languages.cpp = Prism.languages.extend('c', {
 	'class-name': {
-		pattern: /(\b(?:class|enum|struct)\s+)\w+/,
+		pattern: /(\b(?:class|enum|struct)\s+)(?!class|enum|struct)\w+/,
 		lookbehind: true
 	},
 	'keyword': /\b(?:alignas|alignof|asm|auto|bool|break|case|catch|char|char8_t|char16_t|char32_t|class|compl|concept|const|consteval|constexpr|constinit|const_cast|continue|co_await|co_return|co_yield|decltype|default|delete|do|double|dynamic_cast|else|enum|explicit|export|extern|float|for|friend|goto|if|inline|int|int8_t|int16_t|int32_t|int64_t|uint8_t|uint16_t|uint32_t|uint64_t|long|mutable|namespace|new|noexcept|nullptr|operator|private|protected|public|register|reinterpret_cast|requires|return|short|signed|sizeof|static|static_assert|static_cast|struct|switch|template|this|thread_local|throw|try|typedef|typeid|typename|union|unsigned|using|virtual|void|volatile|wchar_t|while)\b/,

tests/languages/cpp/class-name_feature.test

@@ -2,14 +2,16 @@ class Foo
 class Foo_bar
 struct foo
 enum bar
+enum class FooBar
 
 ----------------------------------------------------
 
 [
 	["keyword", "class"], ["class-name", "Foo"],
 	["keyword", "class"], ["class-name", "Foo_bar"],
 	["keyword", "struct"], ["class-name", "foo"],
-	["keyword", "enum"], ["class-name", "bar"]
+	["keyword", "enum"], ["class-name", "bar"],
+	["keyword", "enum"], ["keyword", "class"], ["class-name", "FooBar"]
 ]
 
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