Support multiple FOREIGN KEY

[matiasmorant]

column employee.department refers to department.id and
column employee.boss refers to bosses.id

so table employee has 2 FOREIGN keys:

CREATE TABLE employee (
    id TEXT,
    department TEXT,
    boss TEXT,
    FOREIGN KEY(department) REFERENCES department(id) ON UPDATE RESTRICT ON DELETE CASCADE,
    FOREIGN KEY(boss) REFERENCES boss(id) ON UPDATE RESTRICT ON DELETE CASCADE
)

but only 1 FOREIGN KEY is supported, and I'm hitting

pypika/pypika/queries.py

Line 1903 in a7b01da

raise AttributeError("'Query' object already has attribute foreign_key")

[alisoufali]

I've encountered same issue.