Bump mini_racer from 0.2.14 to 0.2.15 (#9130)

* Bump mini_racer from 0.2.14 to 0.2.15

Bumps [mini_racer](https://github.com/discourse/mini_racer) from 0.2.14 to 0.2.15.
- [Release notes](https://github.com/discourse/mini_racer/releases)
- [Changelog](https://github.com/rubyjs/mini_racer/blob/master/CHANGELOG)
- [Commits](https://github.com/discourse/mini_racer/compare/v0.2.14...v0.2.15)

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

* Bump mini_racer from 0.2.14 to 0.2.15 (Update vendor/cache)

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Gemfile

@@ -61,7 +61,7 @@ gem "jquery-rails", "~> 4.4" #  A gem to automate using jQuery with Rails
 gem "kaminari", "~> 1.2" # A Scope & Engine based, clean, powerful, customizable and sophisticated paginator
 gem "katex", "~> 0.6.0" # This rubygem enables you to render TeX math to HTML using KaTeX. It uses ExecJS under the hood
 gem "liquid", "~> 4.0" # A secure, non-evaling end user template engine with aesthetic markup
-gem "mini_racer", "~> 0.2.14" # Minimal embedded v8
+gem "mini_racer", "~> 0.2.15" # Minimal embedded v8
 # gem "miro", "~> 0.4" # Extract colors from image
 gem "nokogiri", "~> 1.10" # HTML, XML, SAX, and Reader parser
 gem "octokit", "~> 4.16" # Simple wrapper for the GitHub API

Gemfile.lock

@@ -503,7 +503,7 @@ GEM
     mini_magick (4.10.1)
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
-    mini_racer (0.2.14)
+    mini_racer (0.2.15)
       libv8 (> 7.3)
     minitest (5.14.1)
     momentjs-rails (2.20.1)
@@ -956,7 +956,7 @@ DEPENDENCIES
   liquid (~> 4.0)
   listen (~> 3.2)
   memory_profiler (~> 0.9)
-  mini_racer (~> 0.2.14)
+  mini_racer (~> 0.2.15)
   nakayoshi_fork (~> 0.0.4)
   nokogiri (~> 1.10)
   octokit (~> 4.16)