Bump wicked_pdf from 2.8.1 to 2.8.2

Bumps [wicked_pdf](https://github.com/mileszs/wicked_pdf) from 2.8.1 to 2.8.2.
- [Release notes](https://github.com/mileszs/wicked_pdf/releases)
- [Changelog](https://github.com/mileszs/wicked_pdf/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mileszs/wicked_pdf/commits)

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

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

Gemfile.lock

@@ -796,8 +796,9 @@ GEM
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
-    wicked_pdf (2.8.1)
+    wicked_pdf (2.8.2)
       activesupport
+      ostruct
     wkhtmltopdf-binary-ng (0.12.6.6)
     xpath (3.2.0)
       nokogiri (~> 1.8)