Bump ejs, hexo-generator-searchdb and hexo-renderer-ejs

Bumps [ejs](https://github.com/mde/ejs) to 3.1.8 and updates ancestor dependencies [ejs](https://github.com/mde/ejs), [hexo-generator-searchdb](https://github.com/next-theme/hexo-generator-searchdb) and [hexo-renderer-ejs](https://github.com/hexojs/hexo-renderer-ejs). These dependencies need to be updated together.


Updates `ejs` from 1.0.0 to 3.1.8
- [Release notes](https://github.com/mde/ejs/releases)
- [Changelog](https://github.com/mde/ejs/blob/main/CHANGELOG.md)
- [Commits](https://github.com/mde/ejs/commits/v3.1.8)

Updates `hexo-generator-searchdb` from 1.0.8 to 1.4.1
- [Release notes](https://github.com/next-theme/hexo-generator-searchdb/releases)
- [Commits](https://github.com/next-theme/hexo-generator-searchdb/commits/v1.4.1)

Updates `hexo-renderer-ejs` from 0.3.1 to 2.0.0
- [Release notes](https://github.com/hexojs/hexo-renderer-ejs/releases)
- [Commits](hexojs/hexo-renderer-ejs@0.3.1...2.0.0)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: indirect
- dependency-name: hexo-generator-searchdb
  dependency-type: direct:production
- dependency-name: hexo-renderer-ejs
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>