Fix MySQL DELETE using CONCAT_WS preventing index usage #3846

Job	Run time
changes	9s
test-dbt-versions (1.8)	1m 35s
test-dbt-versions (1.4)	1m 29s
test-dbt-versions (1.3)	1m 43s
test-dbt-versions (1.5)	1m 35s
test-dbt-versions (1.7)	1m 45s
test-dbt-versions (1.6)	1m 41s
test-dbt-versions (1.10)	1m 48s
test-dbt-versions (1.9)	1m 50s
test-vscode	-1s
test-vscode-e2e	-7s
cicd-tests-windows	9m 30s
doc-tests	36s
style-and-cicd-tests (3.13)	18m 39s
migration-test	1m 30s
style-and-cicd-tests (3.10)	23m 31s
style-and-cicd-tests (3.12)	24m 24s
style-and-cicd-tests (3.11)	23m 48s
style-and-cicd-tests (3.9)	23m 56s
engine-tests-docker (spark)	5m 3s
engine-tests-docker (mysql)	1m 49s
engine-tests-docker (clickhouse)	2m 57s
engine-tests-docker (starrocks)	2m 48s
engine-tests-docker (risingwave)	3m 20s
engine-tests-docker (trino)	8m 23s
engine-tests-docker (duckdb)	1m 38s
engine-tests-docker (postgres)	2m 16s
engine-tests-docker (mssql)	1m 47s
ui-test	-1s
ui-style	-1s
engine-tests-cloud	0s
	2h 49m 20s

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