chore(deps): bump the ruby group with 3 updates

Bumps the ruby group with 3 updates: [html2rss](https://github.com/html2rss/html2rss), [html2rss-configs](https://github.com/html2rss/html2rss-configs) and [kramdown](https://github.com/gettalong/kramdown).


Updates `html2rss` from `4206a01` to `c686d73`
- [Release notes](https://github.com/html2rss/html2rss/releases)
- [Commits](html2rss/html2rss@4206a01...c686d73)

Updates `html2rss-configs` from `f63f74f` to `905ca2a`
- [Commits](html2rss/html2rss-configs@f63f74f...905ca2a)

Updates `kramdown` from 2.4.0 to 2.5.1
- [Release notes](https://github.com/gettalong/kramdown/releases)
- [Changelog](https://github.com/gettalong/kramdown/blob/master/doc/news.page)
- [Commits](https://github.com/gettalong/kramdown/commits)

---
updated-dependencies:
- dependency-name: html2rss
  dependency-type: direct:production
  dependency-group: ruby
- dependency-name: html2rss-configs
  dependency-type: direct:production
  dependency-group: ruby
- dependency-name: kramdown
  dependency-type: indirect
  update-type: version-update:semver-minor
  dependency-group: ruby
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -1,13 +1,13 @@
 GIT
   remote: https://github.com/html2rss/html2rss-configs.git
-  revision: f63f74f8805177d0237a04f64235785906fa54ba
+  revision: 905ca2a7da7d5cbf63d5265f8b70c64563957252
   specs:
     html2rss-configs (0.2.0)
       html2rss
 
 GIT
   remote: https://github.com/html2rss/html2rss.git
-  revision: 4206a013d1afe66373c3c1b0a4cc7984b06b2e67
+  revision: c686d733f1f56b0aad7c9817d33c97327490c094
   specs:
     html2rss (0.15.0)
       addressable (~> 2.7)
@@ -99,8 +99,8 @@ GEM
       jekyll-include-cache
       jekyll-seo-tag (>= 2.0)
       rake (>= 12.3.1)
-    kramdown (2.4.0)
-      rexml
+    kramdown (2.5.1)
+      rexml (>= 3.3.9)
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     language_server-protocol (3.17.0.3)