Wrong Migration of catalog/seo/product_url_suffix and catalog/seo/category_url_suffix

### Preconditions

1. Magento 1.9.4.4
2. Magento 2.3.4
3. Data Migration Tool 2.3.4

### Steps to reproduce

1. Set the config under the path `catalog/seo/product_url_suffix` to `/`
2. Migrate the settings with the data migration tool
3. Check the migrated value of `catalog/seo/product_url_suffix`

### Expected result

1. I would assume, that the value remains `/`

### Actual result

1. The migrated value is `./`

### Additional notes
The function, which handles that is `\Migration\Handler\Settings\UrlSuffix::handle` The dot is added there, but I can not really understand why this is done.
It actually leads to wrong entries in url_rewrite table, as soon as one adds a new product.

Start with Migration\Handler\Settings\UrlSuffix::handle, which the issue identifies as adding the dot during migration. Reproduce the migration with catalog/seo/product_url_suffix set to /, then verify that the migrated value remains / and does not create incorrect url_rewrite entries when a product is added.

Written by the indexing model from the issue text.