Arkode incorrect first step for Euler method

Bug Description

Arkode with Euler method specified by Butcher table incorrectly calculates first step. 2nd and following steps are calculated correctly.

Steps to reproduce

Run code below

dt = 0.05
tf = dt*3
y0 = 20

function dydt = odefun(t,y)
    dydt = -y
endfunction

t1 = 0:dt:tf
y1 = y0
for ii=2:size(t1,"*")
y1(ii) = y1(ii-1) + dt*odefun(t1(ii-1), y1(ii-1))
end

[t2,y2] = arkode(odefun,[0 tf],y0,ERKButcherTab=[0 0;1 1],fixedStep=dt);

plot(t1,y1,t2,y2)
legend("ad hoc Euler method","arkode")

What is the expected correct behavior?

Correct integration

Error log

No error

Notes

Other tested methods - Heun, Midpoint, Ralston, RK4 - do not suffer by this bug when specified by Butcher table