fix: api/Gemfile & api/Gemfile.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-RUBY-ACTIONVIEW-560837
- https://snyk.io/vuln/SNYK-RUBY-LOOFAH-474102
- https://snyk.io/vuln/SNYK-RUBY-NOKOGIRI-534637
- https://snyk.io/vuln/SNYK-RUBY-NOKOGIRI-552159
- https://snyk.io/vuln/SNYK-RUBY-RACK-538324
- https://snyk.io/vuln/SNYK-RUBY-RACKCORS-534477

api/Gemfile

@@ -32,17 +32,17 @@ source 'https://rubygems.org'
 
 ruby '2.6.3'
 
-gem 'rails', '>= 5.2.2.1'
+gem 'rails', '>= 5.2.4.2'
 
-gem 'activeadmin', '>= 1.4.3'
+gem 'activeadmin', '>= 2.2.0'
 gem 'addressable'
 gem 'bcrypt'
 gem 'cf-app-utils'
 gem 'devise', '>= 4.7.1'
 gem 'friendly_id'
-gem 'inherited_resources', '>= 1.9.0'
+gem 'inherited_resources', '>= 1.11.0'
 gem 'jbuilder'
-gem 'premailer-rails', '>= 1.10.2'
+gem 'premailer-rails', '>= 1.10.3'
 gem 'puma', '>= 3.12.4'
 gem 'rack-cors', '>= 1.0.5', require: 'rack/cors'
 gem 'rack-ssl'
@@ -51,7 +51,7 @@ gem 'uglifier'
 gem 'jwt'
 
 group :development, :test do
- gem 'dotenv-rails', '>= 2.7.0'
+ gem 'dotenv-rails', '>= 2.7.5'
  gem 'pry'
  gem 'pry-byebug'
  gem 'rspec-rails', '>= 3.8.2'