Bump chartkick from 4.2.1 to 5.1.2

Bumps [chartkick](https://github.com/ankane/chartkick) from 4.2.1 to 5.1.2.
- [Changelog](https://github.com/ankane/chartkick/blob/master/CHANGELOG.md)
- [Commits](ankane/chartkick@v4.2.1...v5.1.2)

---
updated-dependencies:
- dependency-name: chartkick
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile

@@ -38,7 +38,7 @@ gem 'bootstrap-social-rails', '~> 4.12'
 gem 'bootstrap_form', '~> 2.7'
 gem 'bundler' # Ensure it's available
 # Note: if webpacker is used, see chartkick website for added instructions
-gem 'chartkick', '~> 4.0' # Chart project_stats
+gem 'chartkick', '~> 5.1' # Chart project_stats
 gem 'faraday-retry', '~> 2.1' # Force retry of faraday requests for reliability
 # We no longger use "fastly-rails"; it doesn't support Rails 6+.
 # They recommend switching to the "fastly" gem (aka "fastly-ruby"),

Gemfile.lock

@@ -117,7 +117,7 @@ GEM
       xpath (~> 3.2)
     capybara-slow_finder_errors (0.1.5)
       capybara (~> 3.0)
-    chartkick (4.2.1)
+    chartkick (5.1.2)
     chef-utils (18.6.2)
       concurrent-ruby
     code_analyzer (0.5.5)
@@ -584,7 +584,7 @@ DEPENDENCIES
   bundler
   bundler-audit
   capybara-slow_finder_errors
-  chartkick (~> 4.0)
+  chartkick (~> 5.1)
   codecov
   dotenv-rails (~> 2.7)
   eslintrb