Bump ffi from 1.9.18 to 1.11.1

Bumps [ffi](https://github.com/ffi/ffi) from 1.9.18 to 1.11.1.
- [Release notes](https://github.com/ffi/ffi/releases)
- [Changelog](https://github.com/ffi/ffi/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ffi/ffi/compare/1.9.18...1.11.1)

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/Gemfile.lock b/Gemfile.lock
index b949c38..6db195b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -21,7 +21,7 @@
     execjs (2.7.0)
     faraday (0.13.1)
       multipart-post (>= 1.2, < 3)
-    ffi (1.9.18)
+    ffi (1.11.1)
     forwardable-extended (2.6.0)
     gemoji (3.0.0)
     github-pages (172)