File Upload dont work when extention is in uppercase

If you try to upload a file with name `Foo.CSV` the upload dont work and dont give any feedback to the user.

Issue: https://github.com/OvidijusParsiunas/active-table/blob/main/component/src/elements/files/buttons/importButton/fileImportButtonEvents.ts#L10 dont trigger because it's case sensitiv (".CSV" !== ".csv")