Bump stackprof to 0.2.13

This adds support for generating `d3` flamegraphs

Gemfile

@@ -381,7 +381,7 @@ group :development, :test do
 
   gem 'knapsack', '~> 1.17'
 
-  gem 'stackprof', '~> 0.2.10', require: false
+  gem 'stackprof', '~> 0.2.13', require: false
 
   gem 'simple_po_parser', '~> 1.1.2', require: false
 

Gemfile.lock

@@ -1003,7 +1003,7 @@ GEM
       sprockets (>= 3.0.0)
     sqlite3 (1.3.13)
     sshkey (2.0.0)
-    stackprof (0.2.10)
+    stackprof (0.2.13)
     state_machines (0.5.0)
     state_machines-activemodel (0.7.1)
       activemodel (>= 4.1)
@@ -1340,7 +1340,7 @@ DEPENDENCIES
   spring-commands-rspec (~> 1.0.4)
   sprockets (~> 3.7.0)
   sshkey (~> 2.0)
-  stackprof (~> 0.2.10)
+  stackprof (~> 0.2.13)
   state_machines-activerecord (~> 0.6.0)
   sys-filesystem (~> 1.1.6)
   test-prof (~> 0.10.0)