Improve attributes table

[felixfontein]

• Use same table structure as for options and return values.
• Adds links to attributes (fixes Module/plugin attributes table does not include links #399).

Examples:

• https://ansible.fontein.de/collections/ansible/builtin/add_host_module.html#attributes vs https://docs.ansible.com/ansible/latest/collections/ansible/builtin/add_host_module.html#attributes
• https://ansible.fontein.de/collections/ansible/builtin/assemble_module.html#attributes vs https://docs.ansible.com/ansible/latest/collections/ansible/builtin/assemble_module.html#attributes
• https://ansible.fontein.de/collections/ansible/builtin/assert_module.html#attributes vs https://ansible.fontein.de/collections/ansible/builtin/assert_module.html#attributes
• https://ansible.fontein.de/collections/ansible/builtin/command_module.html#attributes vs https://docs.ansible.com/ansible/latest/collections/ansible/builtin/command_module.html#attributes

[samccann]

can't comment on the code but the output looks fantastic! thanks!

[felixfontein]

@samccann thanks for reviewing this!