Bump gds-sso from 18.1.0 to 19.0.0

Bumps [gds-sso](https://github.com/alphagov/gds-sso) from 18.1.0 to 19.0.0.
- [Changelog](https://github.com/alphagov/gds-sso/blob/main/CHANGELOG.md)
- [Commits](alphagov/gds-sso@v18.1.0...v19.0.0)

---
updated-dependencies:
- dependency-name: gds-sso
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Gemfile.lock

@@ -148,7 +148,7 @@ GEM
       null_logger
       plek (>= 1.9.0)
       rest-client (~> 2.0)
-    gds-sso (18.1.0)
+    gds-sso (19.0.0)
       oauth2 (~> 2.0)
       omniauth (~> 2.1)
       omniauth-oauth2 (~> 1.8)
@@ -239,7 +239,7 @@ GEM
     mysql2 (0.5.5)
     net-http (0.4.1)
       uri
-    net-imap (0.4.9.1)
+    net-imap (0.4.10)
       date
       net-protocol
     net-pop (0.1.2)
@@ -250,7 +250,7 @@ GEM
       net-protocol
     netrc (0.11.0)
     nio4r (2.7.0)
-    nokogiri (1.16.0)
+    nokogiri (1.16.2)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     null_logger (0.0.1)