update crack to remove dependency on safe_yaml which won't run in Ruby 3

Author: Alexander Atkins

Gemfile.lock

@@ -2,14 +2,13 @@ PATH
   remote: .
   specs:
     ruby-pardot (1.4.1)
-      crack (= 0.4.3)
+      crack (= 0.4.4)
       httparty (= 0.18.1)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    crack (0.4.3)
-      safe_yaml (~> 1.0.0)
+    crack (0.4.4)
     diff-lcs (1.4.4)
     fakeweb (1.3.0)
     httparty (0.18.1)
@@ -32,7 +31,6 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.5.0)
     rspec-support (3.5.0)
-    safe_yaml (1.0.5)
 
 PLATFORMS
   ruby
@@ -44,4 +42,4 @@ DEPENDENCIES
   ruby-pardot!
 
 BUNDLED WITH
-   2.2.7
+   2.3.26

ruby-pardot.gemspec

@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
   s.required_rubygems_version = ">= 1.3.6"
   s.rubyforge_project         = "ruby-pardot"
 
-  s.add_dependency 'crack', '0.4.3'
+  s.add_dependency 'crack', '0.4.4'
   s.add_dependency 'httparty', '0.18.1'
 
   s.add_development_dependency "bundler", ">= 1.10"