Bump wicked_pdf from 2.8.0 to 2.8.1

We're also updating the initializer, which contained a few typos that
were fixed in this version [1].

[1] https://github.com/mileszs/wicked_pdf/commit/19b16c5052

Bumps [wicked_pdf](https://github.com/mileszs/wicked_pdf) from 2.8.0 to 2.8.1.
- [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] <support@github.com>

config/initializers/wicked_pdf.rb

@@ -11,7 +11,7 @@
 WickedPdf.configure do |config|
   # Path to the wkhtmltopdf executable: This usually isn't needed if using
   # one of the wkhtmltopdf-binary family of gems.
-  # config.exe_path = '/usr/local/bin/wkhtmltopdf',
+  # config.exe_path = '/usr/local/bin/wkhtmltopdf'
   #   or
   # config.exe_path = Gem.bin_path('wkhtmltopdf-binary', 'wkhtmltopdf')
 
@@ -20,11 +20,11 @@ WickedPdf.configure do |config|
 
   # Layout file to be used for all PDFs
   # (but can be overridden in `render :pdf` calls)
-  # config.layout = 'pdf.html',
+  # config.layout = 'pdf.html'
 
   # Using wkhtmltopdf without an X server can be achieved by enabling the
   # 'use_xvfb' flag. This will wrap all wkhtmltopdf commands around the
   # 'xvfb-run' command, in order to simulate an X server.
   #
-  # config.use_xvfb = true,
+  # config.use_xvfb = true
 end