chore(deps): bump sitemap_generator from 7479883 to 81ab560

Bumps [sitemap_generator](https://github.com/kjvarga/sitemap_generator) from `7479883` to `81ab560`.
- [Commits](kjvarga/sitemap_generator@7479883...81ab560)

---
updated-dependencies:
- dependency-name: sitemap_generator
  dependency-version: 81ab5604423a0ffa99fe17928ce6237282928915
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -1,9 +1,9 @@
 GIT
   remote: https://github.com/kjvarga/sitemap_generator.git
-  revision: 747988328566c84b0b8aa1ab898ababc371284dc
+  revision: 81ab5604423a0ffa99fe17928ce6237282928915
   branch: master
   specs:
-    sitemap_generator (6.4.0)
+    sitemap_generator (7.0.1)
       builder (~> 3.0)
 
 GEM