Return 400 for invalid UTF-8 multipart fields #2274

Job	Run time
windows_test	2m 28s
compile_and_lint	1m 49s
docker_build (linux/arm64, minimal)	6m 0s
docker_build (linux/amd64, duckdb)	5m 8s
docker_build (linux/amd64, minimal)	5m 13s
test (odbc, postgres, Driver=PostgreSQL Unicode;Server=127.0.0.1;Port=5432;Database=sqlpage;UID=r...	2m 17s
test (mssql, mssql, mssql://root:Password123!@127.0.0.1/sqlpage)	2m 5s
test (postgres, postgres, postgres://root:Password123!@127.0.0.1/sqlpage)	2m 12s
docker_build (linux/arm/v7, minimal)	5m 20s
test (mysql, mysql, mysql://root:Password123!@127.0.0.1/sqlpage)	1m 39s
docker_build (linux/arm64, duckdb)	5m 45s
test (oracle, oracle, Driver=Oracle 21 ODBC driver;Dbq=//127.0.0.1:1521/FREEPDB1;Uid=root;Pwd=Pas...	4m 29s
docker_push	0s
	44m 25s

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