Bump gds-api-adapters from 71.8.0 to 71.9.0

Bumps [gds-api-adapters](https://github.com/alphagov/gds-api-adapters) from 71.8.0 to 71.9.0.
- [Release notes](https://github.com/alphagov/gds-api-adapters/releases)
- [Changelog](https://github.com/alphagov/gds-api-adapters/blob/master/CHANGELOG.md)
- [Commits](alphagov/gds-api-adapters@v71.8.0...v71.9.0)

---
updated-dependencies:
- dependency-name: gds-api-adapters
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Gemfile.lock

@@ -113,7 +113,7 @@ GEM
     faraday-net_http (1.0.1)
     faraday-net_http_persistent (1.1.0)
     ffi (1.13.1)
-    gds-api-adapters (71.8.0)
+    gds-api-adapters (71.9.0)
       addressable
       link_header
       null_logger
@@ -325,7 +325,7 @@ GEM
       docile (~> 1.1)
       simplecov-html (~> 0.11)
     simplecov-html (0.12.3)
-    slimmer (15.5.1)
+    slimmer (15.6.1)
       activesupport
       json
       nokogiri (~> 1.7)