fix: #72 allow case insensitive comparision of the extensions list

[JanStevens]

🔗 Linked issue

#72

❓ Type of change

• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Performs the extension validation check without looking at the case by always applying lowercase to the passed in allowed extensions and the file extension itself that needs to be validated.

It improves ergonomics for a developer so we don't have to do things like: png, PNG, jpg, JPG. In the end if you want to allow png you probably also want to allow PNG.

This can be seen as a breaking change but I suspect the impact will be minimal.

Resolves #72

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[thetutlage]

Can we instead normalize the file extension name at the source? Meaning, when we compute the extension we always convert it to lowercase in the following methods.

• https://github.com/adonisjs/bodyparser/blob/11.x/src/utils.ts#L46
• https://github.com/adonisjs/bodyparser/blob/11.x/src/utils.ts#L64

[JanStevens]

Can we instead normalize the file extension name at the source? Meaning, when we compute the extension we always convert it to lowercase in the following methods.

• https://github.com/adonisjs/bodyparser/blob/11.x/src/utils.ts#L46
• https://github.com/adonisjs/bodyparser/blob/11.x/src/utils.ts#L64

Thanks for the suggestion! I've applied the requested changes and updated the new tests to reflect the changes.

[thetutlage]

Wonderful. Now, we guarantee that file.extname will always be normalized beyond validations as well