Address issues related to R2N and LM with R2DH as subsolver for bpdn with the l1 norm

Address the issues related to R2N and LM by using R2DH as sub-solvers for the Basis Pursuit Denoising (BPDN) problem with the $\ell_1$ norm.
See [runtests.jl](https://github.com/JuliaSmoothOptimizers/RegularizedOptimization.jl/blob/master/test/runtests.jl#L148).
