fix(plugin-blog): useBlogCategory() can't return currentItems correctly

[ShuJun-Junical]

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• [x] Read the Contributing Guidelines.
• [x] Provide a description in this PR that addresses what the PR is solving. If this PR is going to solve an existing issue, please reference the issue (e.g. close #123).

What is the purpose of this pull request?

• [x] Bug fix
• [ ] New feature
• [ ] Other

Description

In plugin-blog, when the current path is URLEncoded (e.g. the path contains Chinese), useBlogCategory() will not return currentItems, decodeURIComponent() is added in the judgment so that it can correctly handle Chinese paths.

Screenshots

Before

After

[Mister-Hope]

I would suggest using normalizeRoutePath from vuepress/shared on the right side