This can also work in application.properties:

spring.datasource.hikari.data-source-properties.allowLoadLocalInfile=true

For more Data Source properties (not particular to the engine): https://dev.mysql.com/doc/connector-j/en/connector-j-reference-configuration-properties.html

More info: https://mysqlconnector.net/troubleshooting/load-data-local-infile/#:~:text=To%20allow%20LOAD%20DATA%20LOCAL,connected%20to%20a%20trusted%20server.