Avoid deserializing value on FK check

[max-hoffman]

No description provided.

[max-hoffman]

#benchmark

[github-actions]

@max-hoffman workflow run: https://github.com/dolthub/dolt/actions/runs/6778292045

[github-actions]

@max-hoffman DOLT

test_name	from_latency_median	to_latency_median	is_faster
tpcc-scale-factor-1	144.97	142.39	0

test_name	server_name	server_version	tps	test_name	server_name	server_version	tps	is_faster
tpcc-scale-factor-1	dolt	9d1562e	32.69	tpcc-scale-factor-1	dolt	177eb0a	32.78	0

[github-actions]

@max-hoffman DOLT

read_tests	from_latency_median	to_latency_median	is_faster
covering_index_scan	2.71	2.71	0
groupby_scan	17.32	17.32	0
index_join	5.0	5.0	0
index_join_scan	2.18	2.18	0
index_scan	56.84	55.82	0
oltp_point_select	0.41	0.42	0
oltp_read_only	7.3	7.3	0
select_random_points	0.69	0.69	0
select_random_ranges	0.94	0.94	0
table_scan	56.84	55.82	0
types_table_scan	161.51	158.63	0

write_tests	from_latency_median	to_latency_median	is_faster
oltp_delete_insert	6.79	6.79	0
oltp_insert	3.36	3.36	0
oltp_read_write	14.73	14.73	0
oltp_update_index	3.36	3.36	0
oltp_update_non_index	3.3	3.3	0
oltp_write_only	7.56	7.56	0
types_delete_insert	7.3	7.3	0