fix(smartcolumn-nvim): Add sensible default opts for when not to show colorcolumn

[menoua]

📑 Description

Adds two filetypes (alpha, neo-tree) to the "smartcolumn" plugin's default list of disabled_filetypes (help, text, markdown). As both alpha-nvim and Neo-tree are included in the AstroNvim core and I see no reason why anyone would want a column in either case, I think it's a good idea to add them to the list of disabled filetypes.

ℹ Additional Information

This is the current behavior:

This is after the change:

[github-actions]

Review Checklist

Does this PR follow the [Contribution Guidelines](development guidelines)? Following is a partial checklist:

Proper conventional commit scoping:

• If you are adding a new plugin, the scope would be the name of the category it is being added into. ex. feat(utility): added noice.nvim plugin

• If you are modifying a pre-existing plugin or pack, the scope would be the name of the plugin folder. ex. fix(noice-nvim): fix LSP handler error

• Pull request title has the appropriate conventional commit type and scope where the scope is the name of the pre-existing directory in the project as described above

• README is properly formatted and uses fenced in links with <url> unless they are inside a [title](url)

• Proper usage of opts table rather than setting things up with the config function.