Update bulma-clean-theme requirement from 1.0.3 to 1.1.0

Updates the requirements on [bulma-clean-theme](https://github.com/chrisrhymes/bulma-clean-theme) to permit the latest version.
- [Release notes](https://github.com/chrisrhymes/bulma-clean-theme/releases)
- [Changelog](https://github.com/chrisrhymes/bulma-clean-theme/blob/master/changelog.txt)
- [Commits](chrisrhymes/bulma-clean-theme@v1.0.3...v1.1.0)

---
updated-dependencies:
- dependency-name: bulma-clean-theme
  dependency-type: direct:production
...

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

Gemfile

@@ -1,5 +1,5 @@
 source "https://rubygems.org"
-gem "bulma-clean-theme",  '1.0.3'
+gem "bulma-clean-theme",  '1.1.0'
 # gem "github-pages", group: :jekyll_plugins
 # gem "just-the-docs", "0.8.2" # pinned to the current release
 # gem "just-the-docs"        # always download the latest release