Ensure to use LC_COLLATE=C with sort

As found by @romaricb , bash commands `sort` and `uniq` used in several resource building scripts can merge lines that are different if containing Unicode characters not defined in the current locale collation table (see [this stackexchange question](https://unix.stackexchange.com/questions/17198/where-has-my-uniq-or-sort-u-line-gone-with-some-unicode-characters)). This can be avoided by setting `LC_COLLATE=C` to avoid any collation.

We must ensure `LC_COLLATE=C` is used anywhere `sort -u` or [uniq](url) are used in our scripts.