docs: Update to jekyll-theme-amethyst 1.2.0

Introducing the `<typesense-minibar>` web component.

Ref https://github.com/jquery/typesense-minibar/commits/1.3.1/
Ref https://github.com/qunitjs/jekyll-theme-amethyst/

Author: Krinkle

docs/Gemfile

@@ -2,4 +2,4 @@ source "https://rubygems.org"
 ruby RUBY_VERSION
 
 # To apply changes, run `bundle update`.
-gem "jekyll-theme-amethyst", "1.1.0", group: :jekyll_plugins
+gem "jekyll-theme-amethyst", "1.2.0", group: :jekyll_plugins