vim-patch:8.2.0154: reallocating the list of scripts is inefficient

Problem:    Reallocating the list of scripts is inefficient.
Solution:   Instead of using a growarray of scriptitem_T, store pointers and
            allocate each scriptitem_T separately.  Also avoids that the
            growarray pointers change when sourcing a new script.

21b9e9773d

Co-authored-by: Bram Moolenaar <Bram@vim.org>

src/nvim/cmdexpand.c

@@ -2524,7 +2524,7 @@ static char *get_scriptnames_arg(expand_T *xp FUNC_ATTR_UNUSED, int idx)
     return NULL;
   }
 
-  scriptitem_T *si = &SCRIPT_ITEM(idx + 1);
+  scriptitem_T *si = SCRIPT_ITEM(idx + 1);
   home_replace(NULL, si->sn_name, NameBuff, MAXPATHL, true);
   return NameBuff;
 }