Use cfg(any()) instead of cfg(FALSE) for disabling proc-macro test

Author: Veykril

crates/rust-analyzer/tests/slow-tests/main.rs

@@ -821,7 +821,7 @@ fn main() {
 
 #[test]
 // FIXME: Re-enable once we can run proc-macro tests on rust-lang/rust-analyzer again
-#[cfg(FALSE)]
+#[cfg(any())]
 fn resolve_proc_macro() {
     use expect_test::expect;
     if skip_slow_tests() {