Meta: Ensure the main thread VM is created before use in the CSS fuzzer

Author: https://github.com/trflynn89
Commit: https://github.com/SerenityOS/serenity/commit/5d7a85bc37
Pull-request: https://github.com/SerenityOS/serenity/pull/17896

Meta/Lagom/Fuzzers/FuzzCSSParser.cpp

@@ -17,6 +17,8 @@ Globals::Globals() { Web::Platform::EventLoopPlugin::install(*new Web::Platform:
 
 extern "C" int LLVMFuzzerTestOneInput(uint8_t const* data, size_t size)
 {
+    MUST(Web::Bindings::initialize_main_thread_vm());
+
     // FIXME: There's got to be a better way to do this "correctly"
     auto& vm = Web::Bindings::main_thread_vm();
     (void)Web::parse_css_stylesheet(Web::CSS::Parser::ParsingContext(*vm.current_realm()), { data, size });