`initialization_eqs` example broken in initialization docs

[ArnoStrouwen]

https://docs.sciml.ai/ModelingToolkit/dev/tutorials/initialization/#Initialization-By-Example:-The-Cartesian-Pendulum

prob = ODEProblem(pend, [x => 1], (0.0, 1.5), [g => 1], guesses = [λ => 0, y => 1],
    initialization_eqs = [y ~ 1])
sol = solve(prob, Rodas5P())

┌ Warning: The initialization system is structurally singular. Guess values may significantly affect the initial values of the ODE. The problematic variables are Any[xˍtt(t)].
│ Note that the identification of problematic variables is a best-effort heuristic.

┌ Warning: Potential Rank Deficient Matrix Detected. Attempting to solve using Pivoted QR Factorization.