Fix assertion error in split rewrite during eviction

#0  0x00007fe35886393f in raise () from /lib64/libc.so.6

#1  0x00007fe35884dc95 in abort () from /lib64/libc.so.6

#2  0x0000561158d84ffd in __wt_abort (session=<optimized out>) at src/third_party/wiredtiger/src/os_common/os_abort.c:30

#3  0x0000561159043b12 in __split_multi_inmem (session=0x7fe34b3a7120, orig=0x61d00047b880, multi=0x604000429390, ref=0x60e000369360) at src/third_party/wiredtiger/src/btree/bt_split.c:1454

#4  0x00005611590469da in __wt_split_rewrite (session=0x7fe34b3a7120, ref=0x60e0006ca0a0, multi=0x619002166a80) at src/third_party/wiredtiger/src/btree/bt_split.c:2241

#5  0x0000561158d182d0 in __wt_evict (session=0x7fe34b3a7120, ref=0x60e0006ca0a0, previous_state=3 '\003', flags=<optimized out>) at src/third_party/wiredtiger/src/evict/evict_page.c:368

#6  0x0000561158d0f6a4 in __evict_page (session=<optimized out>, is_server=false) at src/third_party/wiredtiger/src/evict/evict_lru.c:2334

#7  0x0000561158d0c4ac in __wt_cache_eviction_worker (session=<optimized out>, busy=true, readonly=false, pct_full=0) at src/third_party/wiredtiger/src/evict/evict_lru.c:2444

#8  0x0000561158fbbe84 in __cursor_enter (session=<optimized out>) at src/third_party/wiredtiger/src/include/cursor_inline.h:190

#9  __wt_cursor_func_init (cbt=<optimized out>, reenter=255) at src/third_party/wiredtiger/src/include/cursor_inline.h:404

#10 0x0000561158fbcba5 in __wt_btcur_search_near (cbt=<optimized out>, exactp=0x7fe280ffb5f0) at src/third_party/wiredtiger/src/btree/bt_cursor.c:712

#11 0x0000561158cb8d4e in __curfile_search_near (cursor=<optimized out>, exact=0x7fe280ffb5f0) at src/third_party/wiredtiger/src/cursor/cur_file.c:232