Constant MIGRATION_V8

pub const MIGRATION_V8: &str = r#"
CREATE TABLE virtual_currency_balance (
    user_scope    TEXT NOT NULL,
    code          TEXT NOT NULL,
    balance       INTEGER NOT NULL,
    updated_at_ms INTEGER NOT NULL,
    PRIMARY KEY (user_scope, code)
);

CREATE TABLE experiment_exposure (
    user_scope    TEXT NOT NULL,
    experiment_id TEXT NOT NULL,
    variant_id    TEXT NOT NULL,
    exposed_at_ms INTEGER NOT NULL,
    PRIMARY KEY (user_scope, experiment_id, variant_id)
);

UPDATE schema_meta SET version = 8;
"#;