Fix language switcher "eating" part of vocids that end in a langcode (e.g. "interessen" and "en")

[schlawiner]

I happend to have a vocabulary named (vocid) "interessen", which ends in "en", one of the available ui languages.
When switching the UI to German, the "en" ending in the url (/interessen/en/) was replaced with the "de" code, as well as appending another /de. So en was (re)placed twice, leading to broken urls such as /interessde/de/.

I fixed this for now by making the "| replace" filter that rewrites the url not as greedy: instead of any langcode-looking text, it now looks for a slash preceding it (/en instead of just en). This will probably not fix instances where a vocid is exactly the same as one of the langcodes (vocabularies named "en", "de", "fr" etc.) but is good enough for me at the moment.

[sonarcloud]

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[osma]

Thanks! Looks good but needs to be tested.

You are right that's it's possible to end up in trouble by having a vocabulary id that is identical to a language code. The URL pattern for Skosmos doesn't support that case very well.

[osma]

I tested this both with and without the dropdown-style UI language selector. It does exactly what it should, so I'm merging it now. Thanks a lot @schlawiner !