Fix mixed-script values in the ru_RU company name lists

[a-vasyukov]

What is the reason for this PR?

• A new feature
• Fixed an issue

Three values in src/Provider/ru_RU/Company.php mix scripts:

Value	Problem
'-H' ($companyNameSuffixes)	Latin H (U+0048) instead of Cyrillic Н (U+041D)
'Cиб' ($companyElements)	Latin C (U+0043) instead of Cyrillic С (U+0421)
'IT' ($companyElements)	Latin inside an otherwise Cyrillic list

Company names are assembled without separators
({{companyPrefix}} {{companyNameElement}}{{companyNameElement}}{{companyNameSuffix}}), so each of
these produces a mixed-script word: Хмель-H, CибМаш, ITМонтаж. Such strings do not match a
search for their Cyrillic spelling and sort incorrectly — Cиб is never found by Сиб. Each value
lands in roughly 3.6% of generated company names.

'IT' is wrong as data too: a Russian company's registered name is written in Russian, and foreign
words may only appear in Cyrillic transcription, so Russian IT companies are registered as АйТи,
never as IT.

This re-submits the fix from #882, which was approved twice but closed by the stale bot on
2025-05-06, and extends it to the other two values.

Author's checklist

• Follow the Contribution Guide
• New features and changes are documented

Summary of changes

• '-H' → '-Н', 'Cиб' → 'Сиб', 'IT' → 'АйТи'
• add a test asserting that both name lists contain no Latin characters

Regarding "avoid changing existing sets of data": no element is added, removed or reordered, so a
given seed still selects the same positions in the same order. Only the characters inside three
values change — the very characters that are the defect.

The suite stays green: 1416 tests before, 1417 with the new test, no failures.

Review checklist

• All checks have passed
• Changes are added to the CHANGELOG.md
• Changes are approved by maintainer

[a-vasyukov]

Pinging before the stale bot reaches this one — the fix it re-submits (#882) was approved twice and
then closed by that same bot.

If 'IT' → 'АйТи' is what's holding it up, I'll split it out: '-H' and 'Cиб' are plain
Latin-in-Cyrillic typos, 'IT' is a judgement about the data. Say the word and the two homoglyphs
land on their own.

CI has never run here — outside contributors need manual approval.