VPN-5138: Fix pascal case

[mcleinman]

Description

• The translation in xliff showed an id of servers.Mcallen, which later converts into serversMcallen
• However, in the code we were looking for serversMcAllen - we weren’t handling capitalization consistently!
• In update_server_names.py, we are changing the cities to title case: id = city.split(",")[0].strip().title().replace(" ", “”)
• In Localizer::getTranslatedCityName, we have this line: QString i18nCityId = QString("Servers%1").arg(toPascalCase(parsedCityName));
• However, toPascalCase had a bug: words[i] = word.at(0).toUpper() + word.mid(1) (bug introduced here: VPN-5175 - Get languages, currencies and server name translations from the l10n repository strings #9448)
• But, we need to preserve the existing capitalization behavior for language string IDs (used for "how do you translate the word 'Japanese' in a Spanish locale?") as caught by our unit tests.

There is additional bug with Malmö that is part of VPN-5138. This bug is Windows-only. I tried debugging via additional logging in the build (you'll see a bunch of commits related to this, as I needed it to run on TaskCluster), but kept hitting dead ends. I do not have a Windows dev machine, and this would be much easier to debug with one. I've filed this part as https://mozilla-hub.atlassian.net/browse/VPN-6649.

Reference

VPN-5138

Checklist

• My code follows the style guidelines for this project
• I have not added any packages that contain high risk or unknown licenses (GPL, LGPL, MPL, etc. consult with DevOps if in question)
• I have performed a self review of my own code
• I have commented my code PARTICULARLY in hard to understand areas
• I have added thorough tests where needed