Bump brakeman from 4.3.1 to 4.7.2

Bumps [brakeman](https://github.com/presidentbeef/brakeman) from 4.3.1 to 4.7.2.
- [Release notes](https://github.com/presidentbeef/brakeman/releases)
- [Changelog](https://github.com/presidentbeef/brakeman/blob/master/CHANGES.md)
- [Commits](presidentbeef/brakeman@v4.3.1...v4.7.2)

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

Gemfile

@@ -74,7 +74,7 @@ group :development, :test do
   gem 'guard-jasmine', '~> 2.0'
   # We can relax this brakeman dependency after we have deployed a hybrid
   # cookie serializer and allowed a chance for cookies to be stored as JSON.
-  gem 'brakeman', '4.5.1', require: false
+  gem 'brakeman', '4.7.2', require: false
   gem 'rubocop', '0.52.1', require: false
   gem 'rubocop-rspec', '1.22.2', require: false
 end

Gemfile.lock

@@ -71,7 +71,7 @@ GEM
     backports (3.15.0)
     bootsnap (1.4.5)
       msgpack (~> 1.0)
-    brakeman (4.5.1)
+    brakeman (4.7.2)
     builder (3.2.4)
     byebug (11.0.1)
     canvas_oauth_engine (2.1.2)
@@ -458,7 +458,7 @@ PLATFORMS
 DEPENDENCIES
   aws-sdk-s3 (~> 1.0)
   bootsnap (~> 1.0)
-  brakeman (= 4.5.1)
+  brakeman (= 4.7.2)
   bundler (>= 1.7.10)
   byebug
   canvas_oauth_engine (~> 2.1.2)