How to set a postgres configuration with Diesel? I'm trying get RLS to work

Question

I have this "almost" working. I have setup all the infrastructure in my migrations:

-- tenant
CREATE TABLE tenant (
    tenant_id int primary key generated always as identity,
    name VARCHAR(255) UNIQUE,
    status VARCHAR(64) CHECK (status IN ('active', 'suspended', 'disabled'))
);

-- Turn on RLS
ALTER TABLE tenant ENABLE ROW LEVEL SECURITY;

-- Restrict read and write actions so tenants can only see their rows
-- This policy implies a WITH CHECK that matches the USING clause
CREATE POLICY tenant_isolation_policy ON tenant
USING (tenant_id = current_setting('app.current_tenant')::int);

-- tenant_user
CREATE EXTENSION pgcrypto; -- needed for password

CREATE TABLE tenant_user (
    user_id int primary key generated always as identity,
    tenant_id int NOT NULL REFERENCES tenant (tenant_id) ON DELETE RESTRICT,
    email VARCHAR(255) NOT NULL UNIQUE,
    given_name VARCHAR(255) NOT NULL CHECK (given_name <> ''),
    family_name VARCHAR(255) NOT NULL CHECK (family_name <> ''),
    password TEXT NOT NULL,
    is_verified BOOL DEFAULT 'f',
    created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
);

-- Restrict read and write actions so tenants can only see their rows
-- This policy implies a WITH CHECK that matches the USING clause
ALTER TABLE tenant_user ENABLE ROW LEVEL SECURITY;

-- Restrict read and write actions so tenants can only see their rows
-- This policy implies a WITH CHECK that matches the USING clause
CREATE POLICY tenant_user_isolation_policy ON tenant_user
USING (tenant_id = current_setting('app.current_tenant')::int);

This is the part I can't figure out how to get working with Diesel. I can do this from my SQL editor;

-- with super-user account
INSERT INTO tenant (name, status) VALUES ('tenant1', 'active');
INSERT INTO tenant (name, status) VALUES ('tenant2', 'active');

-- with non super-user account
SET app.current_tenant = 1;
INSERT INTO tenant_user (email, password, tenant_id, given_name, family_name) VALUES ('[email protected]', crypt('test', gen_salt('bf')), 1, 'Test', 'User');
SELECT * FROM tenant_user WHERE ('[email protected]' in (email)) AND password = crypt('test', password);
-- I get back the user I created
SET app.current_tenant = 2;
SELECT * FROM tenant_user WHERE ('[email protected]' in (email)) AND password = crypt('test', password);
-- I don't get back the user, this is what I expected

However, I can't seem to figure out how to do the SET configuration from Diesel. I tried something like this:

let sql = "SET app.current_tenant = 1";
let query = sql_query(sql);
let result = query.execute(&conn);

Which seems to run, but then my follow-up query does not return successfully as I was expecting:

sql_function!(fn crypt(passwd: Text, salt: Text) -> Text);
tenant_user::table()
  .filter(email.eq(msg.email))
  .filter(password.eq(crypt(msg.password, password)))
  .get_result::<TenantUser>(&conn)

My query does work if I run it with the super-user account. So I think I'm missing something. Either my SET command is not running properly or I'm missing something else. Any help you could provide would be much appreciated.