Add key of the drowned library

[murilo09]

Description

Key of the Drowned Library now working

Behaviour

Actual

When using the Key of the Drowned Library in the Seashell Bookcase nothing happens

Expected

Now, when using the Key of the Drowned Library in the Seashell Bookcase can give you one of the three Books.

Fixes

#728

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I checked the PR checks reports
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works

[majestyotbr]

Can you follow the name pattern of the file?
Change name from seashellKey.lua to seashell_key.lua
Thanks.

[majestyotbr]

It's working but also appears "You cannot use this object." in the game window.

[majestyotbr]

Tested and working fine now.