dark_prismarine_stairs could be converted to stone_brick_stairs instead of cobblestone_stairs

[joserobjr]

Is your feature request related to a problem? Please describe.
The stone_brick_stairs matches the the dark prismarine theme better then cobblestone stairs. Cobblestone seems to raw to dark prismarine blocks.

Describe the solution you'd like
Convert dark_prismarine_stairs to stone_brick_stairs

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
No alternatives..

Additional context
Add any other context or screenshots about the feature request here.