Bump nanoc from 4.12.17 to 4.12.18

Bumps [nanoc](https://github.com/nanoc/nanoc) from 4.12.17 to 4.12.18.
- [Release notes](https://github.com/nanoc/nanoc/releases)
- [Commits](nanoc/nanoc@nanoc-cli-v4.12.17...nanoc-cli-v4.12.18)

---
updated-dependencies:
- dependency-name: nanoc
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -55,25 +55,25 @@ GEM
     method_source (1.0.0)
     mini_portile2 (2.8.4)
     multi_json (1.15.0)
-    nanoc (4.12.17)
+    nanoc (4.12.18)
       addressable (~> 2.5)
       colored (~> 1.2)
       nanoc-checking (~> 1.0, >= 1.0.2)
-      nanoc-cli (= 4.12.17)
-      nanoc-core (= 4.12.17)
+      nanoc-cli (= 4.12.18)
+      nanoc-core (= 4.12.18)
       nanoc-deploying (~> 1.0)
       parallel (~> 1.12)
       tty-command (~> 0.8)
       tty-which (~> 0.4)
     nanoc-checking (1.0.2)
       nanoc-cli (~> 4.12, >= 4.12.4)
       nanoc-core (~> 4.12, >= 4.12.4)
-    nanoc-cli (4.12.17)
+    nanoc-cli (4.12.18)
       cri (~> 2.15)
       diff-lcs (~> 1.3)
-      nanoc-core (= 4.12.17)
+      nanoc-core (= 4.12.18)
       zeitwerk (~> 2.1)
-    nanoc-core (4.12.17)
+    nanoc-core (4.12.18)
       concurrent-ruby (~> 1.1)
       ddmetrics (~> 1.0)
       ddplugin (~> 1.0)