Fix CI

Author: YingboMa

src/Blocks/continuous.jl

@@ -626,7 +626,7 @@ See also [`StateSpace`](@ref) which handles MIMO systems, as well as [ControlSys
     if nx == 0
         eqs = [y ~ d * u]
     else
-        eqs = [D(x_scaled[1]) ~ (-a[2:na]'x_scaled + a_end * u) / a[1]
+        eqs = Equation[D(x_scaled[1]) ~ (-a[2:na]'x_scaled + a_end * u) / a[1]
                D.(x_scaled[2:nx]) .~ x_scaled[1:(nx - 1)]
                y ~ ((bb[2:na] - d * a[2:na])'x_scaled) / a_end + d * u
                x .~ x_scaled ./ a_end]