Fixes issue #463

[EricGusmao]

This pull request includes several updates to the TailwindCSS Rails templates and gemspec file. The most important changes involve updating the TailwindCSS classes for form elements and specifying a version constraint for the tailwindcss-ruby dependency.

Updates to TailwindCSS classes:

• lib/generators/tailwindcss/authentication/templates/app/views/passwords/edit.html.erb: Changed the class attribute of password_field and password_confirmation elements to use shadow-sm instead of shadow and outline-hidden instead of outline-none.
• lib/generators/tailwindcss/authentication/templates/app/views/passwords/new.html.erb: Updated the class attribute of the email_field element to use shadow-sm and outline-hidden instead of shadow and outline-none.
• lib/generators/tailwindcss/authentication/templates/app/views/sessions/new.html.erb: Modified the class attribute of email_field and password_field elements to use shadow-sm instead of shadow.
• lib/generators/tailwindcss/scaffold/templates/_form.html.erb.tt: Updated the class attribute of various form elements to use shadow-sm and outline-hidden instead of shadow and outline-none.

Dependency version update:

• tailwindcss-rails.gemspec: Added a version constraint to the tailwindcss-ruby dependency, specifying version ~> 4.0.

[EricGusmao]

Closing this PR as the changes have been cherry-picked into another branch.