patch 8.2.2968: Vim9: memory leak

Problem:    Vim9: memory leak
Solution:   Unreference pt_outer of partial.

src/eval.c

@@ -4301,6 +4301,9 @@ partial_free(partial_T *pt)
     else
 	func_ptr_unref(pt->pt_func);
 
+    // "out_up" is no longer used, decrement refcount on partial that owns it.
+    partial_unref(pt->pt_outer.out_up_partial);
+
     // Decrease the reference count for the context of a closure.  If down
     // to the minimum it may be time to free it.
     if (pt->pt_funcstack != NULL)

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2968,
 /**/
     2967,
 /**/