Plugin-blog: a category of front matter does not be recognized

[tkzwhr]

Bug report

Version

v1.0.0-alpha.9

Steps to reproduce

to create a post and write - category: foo on front matter.

What is expected?

contains the category in $categories.

What is actually happening?

not contained.

Other relevant information

maybe simple mistake:

vuepress/packages/@vuepress/plugin-blog/index.js

Line 109 in 19e73d7

handleCategory(categories, key)

correctly:

handleCategory(category, key)

[ulivz]

Yes, welcome to create a PR.

[ulivz]

Release at 1.0.0-alpha.12.