Bump arbre from 1.6.0 to 1.7.0 in /railseventstore.org

Bumps [arbre](https://github.com/activeadmin/arbre) from 1.6.0 to 1.7.0.
- [Release notes](https://github.com/activeadmin/arbre/releases)
- [Changelog](https://github.com/activeadmin/arbre/blob/master/CHANGELOG.md)
- [Commits](activeadmin/arbre@v1.6.0...v1.7.0)

---
updated-dependencies:
- dependency-name: arbre
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

railseventstore.org/Gemfile.lock

@@ -1,16 +1,16 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (7.0.7.2)
+    activesupport (7.0.8)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
     addressable (2.8.5)
       public_suffix (>= 2.0.2, < 6.0)
-    arbre (1.6.0)
-      activesupport (>= 3.0.0, < 7.1)
-      ruby2_keywords (>= 0.0.2, < 1.0)
+    arbre (1.7.0)
+      activesupport (>= 3.0.0)
+      ruby2_keywords (>= 0.0.2)
     backports (3.24.1)
     base64 (0.1.1)
     coffee-script (2.4.1)