fix: deps for newer ruby versions

Author: Justintime50

.github/workflows/ci.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        rubyversion: ['2.7', '3.0', '3.1', '3.2', '3.3', '3.4']
+        rubyversion: ['2.7', '3.0', '3.1', '3.2', '3.3', '3.4', '4.0']
     steps:
       - uses: actions/checkout@v5
       - uses: ruby/setup-ruby@v1

easypost.gemspec

@@ -20,6 +20,8 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
   spec.required_ruby_version = '>= 2.7'
 
+  spec.add_dependency 'base64'
+
   spec.add_development_dependency 'abbrev', '~> 0.1'
   spec.add_development_dependency 'benchmark', '~> 0.4'
   spec.add_development_dependency 'bigdecimal', '~> 3'
@@ -34,6 +36,6 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'simplecov', '~> 0.22'
   spec.add_development_dependency 'simplecov-lcov', '~> 0.8'
   spec.add_development_dependency 'typhoeus', '~> 1.4'
-  spec.add_development_dependency 'vcr', '~> 6.3'
+  spec.add_development_dependency 'vcr', '~> 6.4'
   spec.add_development_dependency 'webmock', '~> 3.25'
 end