Liquibase & Spring Boot - Create function that reads from file - Spring does not see the file

Question

I have a simple .csv file that has 2 columns: username, value. I want to create a function that reads the file, checks if user exists by username and executes a single insert command if it does.
I have created a function, but it seems Spring Boot does not see the file :(
Any help? Or maybe there's a better way to do that? I can't execute multiple inserts with nested select since there's a constraint that the userId field in table descriptions cannot be null.

Here's the code:

<changeSet id="333 - Setup user descriptions" author="me">
    <sql>
        CREATE OR REPLACE FUNCTION import_user_description()
        RETURNS void
        LANGUAGE plpgsql AS
        '
        DECLARE
        userId integer;

        BEGIN

        create temp table temp (
        username character varying,
        value character varying
        );

        execute format('copy temp from %L with delimiter '','' quote ''"'' csv ', ./imports/users/descriptions.csv);

        FOR name IN (select username from temp)
        LOOP

        if exists (select id from users where username = name)
        
        select id into userId from users where username = name;
        INSERT INTO descriptions (userId, description) VALUES (userId, description);

        end if; 
        END LOOP;

        drop table temp;

        END';
        select import_user_description();
    </sql>
</changeSet>

I have also tried COPY temp FROM './imports/users/descriptions.csv' WITH (FORMAT csv); but keep getting an error...

ERROR: syntax error at or near "." Position: 350