Update Russian translation in i18/ru.toml (#816)

### Prerequisites

Put an `x` into the box(es) that apply:

- [x] This pull request fixes a bug.
- [ ] This pull request adds a feature.
- [ ] This pull request introduces breaking change.

### Description

Correcting the Russian translation.

### Issues Resolved

Slight translation inaccuracies.

### Checklist

Put an `x` into the box(es) that apply:

#### General

- [x] Describe what changes are being made
- [x] Explain why and how the changes were necessary and implemented
respectively
- [ ] Reference issue with `#<ISSUE_NO>` if applicable

#### Resources

- [ ] If you have changed any SCSS code, run `make release` to
regenerate all CSS files

#### Contributors

- [x] Add yourself to `CONTRIBUTORS.md` if you aren't on it already

i18n/ru.toml

@@ -1,18 +1,18 @@
 [categories]
 one = "категория"
-other = "categories"
+other = "категории"
 
 [tags]
 one = "тэг"
-other = "tags"
+other = "тэги"
 
 [series]
-one = "серии"
-other = "series"
+one = "серия"
+other = "серии"
 
 [authors]
 one = "автор"
-other = "authors"
+other = "авторы"
 
 [posts]
 other = "статьи"
@@ -32,7 +32,7 @@ other = "Извините, но этой страницы не существу
 other = "Можете вернуться обратно на <a href=\"{{ . }}\">домашнюю страницу</a>."
 
 [licensed_under]
-other = "Licensed under"
+other = "Лицензирован по"
 
 [powered_by]
 other = "Работает на"
@@ -41,25 +41,25 @@ other = "Работает на"
 other = "Также смотреть"
 
 [note]
-other = "note"
+other = "заметка"
 
 [tip]
-other = "tip"
+other = "совет"
 
 [example]
-other = "example"
+other = "пример"
 
 [question]
-other = "question"
+other = "вопрос"
 
 [info]
-other = "info"
+other = "информация"
 
 [warning]
-other = "warning"
+other = "предупреждение"
 
 [error]
-other = "error"
+other = "ошибка"
 
 [link_to_heading]
-other = "Link to heading"
+other = "Ссылка на заголовок"