Upd link to haddock-restraints —pml documentation in advances protein-DNA tutorial (when available)

[AnnaKravchenko]

In haddock2.4 advanced protein-DNA tutorial, replace current link under documentation to an actual documentation page describing the use of —pml flag in haddock-restraints. Current link (haddocking/haddock-restraints#47) points to the closed github issue, since documentation is on the way.

Link location in tuto:
education/HADDOCK24/HADDOCK24-protein-DNA-advanced/index.md
Line 515:
Note that AIRviewer is not the only way to visualize the restraints network. You can also use haddock-restraints with the --pml flag. See the documentation for more details.