Remove check for shared root arrays

All shared root arrays should not be on the transient heap.
ary_make_shared evacuates arrays from the transient heap when creating
shared roots.

array.c

@@ -452,15 +452,13 @@ static inline void
 rb_ary_transient_heap_evacuate_(VALUE ary, int transient, int promote)
 {
     if (transient) {
+        assert(!ARY_SHARED_ROOT_P(ary));
+
         VALUE *new_ptr;
         const VALUE *old_ptr = ARY_HEAP_PTR(ary);
         long capa = ARY_HEAP_CAPA(ary);
         long len  = ARY_HEAP_LEN(ary);
 
-        if (ARY_SHARED_ROOT_P(ary)) {
-            capa = len;
-        }
-
         assert(ARY_OWNS_HEAP_P(ary));
         assert(RARRAY_TRANSIENT_P(ary));
         assert(!ARY_PTR_USING_P(ary));