fix:changed the judgement of whether it has been injected

[mRNA16]

What does it do?

When I introduced the Hexo injector in my blog post: 'Here we can see that between and there are many div blocks that we injected using the injector, and at the same time, between and there are JavaScript script blocks and canvas elements that we injected. I believe by now you can understand the functionality of the injector.' However, I found that the custom effects implemented through the injector were not working, so I checked the source code and found an issue with the logic that determines whether the injector has inserted content. When content like hexo injector body exists in my article, the injector mistakenly thinks it has already been inserted.
I tried to ensure that the comments and tags are tightly connected by using the condition (flag==='head_begin' && /<head.*?>\s*<!-- hexo injector head_begin start -->[\S\s]*<!-- hexo injector head_begin end -->/.test(input)), but this causes the test cases in the test to fail. So, I changed the condition to if (input.includes(, it still causes the injector to fail. Therefore, I still have some doubts about the condition and test cases. Will a situation like really occur in thetest? I don’t think it will in practical applications. If this situation doesn’t occur, then using the regex condition (flag==='head_begin' && /<head.?>\s[\S\s]*/.test(input))` to check if the comment and tag are connected seems like a better choice, as it can handle all the cases mentioned above. Of course, this is just my thought, and I would appreciate any guidance if I'm mistaken.

Screenshots

My homepage has

blocks inserted within the tag.

But after mentioning and in the article, the injector stopped working."

Pull request tasks

• Add test cases for the changes.
• Passed the CI test.

[github-actions]

How to test

git clone -b injector_change https://github.com/mRNA16/hexo.git
cd hexo
npm install
npm test

[mRNA16]

I have made modifications to node_modules/hexo/dist/extend/injector.js locally. Both methods I proposed can solve the above issue. The changes I suggested should fix the bug. Please review my PR，thx！