Rewrite `language-list` examples in instructions without using the pipe

[angelikatyborska]

The pipe operator is only taught later in the concept tree (at strings (high school sweetheart) and shouldn't be used in the code examples in exercises that come before. Please rewrite those examples without the pipe.

https://github.com/exercism/elixir/blob/main/exercises/concept/language-list/.docs/instructions.md?plain=1#L20-L21