Remove wrong assertion (#1117)

Introduced in commit 97c9186 from April 2024. Looks like a code move
gone wrong.

Author: bnoordhuis

quickjs.c

@@ -3215,7 +3215,6 @@ static const char *JS_AtomGetStrRT(JSRuntime *rt, char *buf, int buf_size,
         JSAtomStruct *p = rt->atom_array[atom];
         *buf = '\0';
         if (atom_is_free(p)) {
-            assert(!atom_is_free(p));
             snprintf(buf, buf_size, "<free %x>", atom);
         } else if (p != NULL) {
             JSString *str = p;