TestDeleteCookies fails with go 1.14.9

[Andrew Gaul]

$ go test
--- FAIL: TestDeleteCookies (0.00s)
    require.go:44:
                Error Trace:    handlers_test.go:460
                Error:          "[k3=v3]" does not contain "k1="
                Test:           TestDeleteCookies
FAIL
exit status 1
FAIL    github.com/ahmetb/go-httpbin    2.229s

[Ahmet Alp Balkan]

If you got a fix, it's appreciated! I haven't looked at the code in a while.