Fix Ruby 2.7 issue

Author: jasonbosco

.rubocop.yml

@@ -2,6 +2,7 @@ require: rubocop-rspec
 
 AllCops:
   NewCops: enable
+  TargetRubyVersion: 2.7
 
 Style/Documentation:
   Enabled: false

spec/typesense/collections_spec.rb

@@ -36,7 +36,7 @@
   describe '#create' do
     it 'creates a collection and returns it' do
       # since num_documents is a read-only attribute
-      schema_for_creation = company_schema.except('num_documents')
+      schema_for_creation = company_schema.reject { |key, _| key == 'num_documents' }
 
       stub_request(:post, Typesense::ApiCall.new(typesense.configuration).send(:uri_for, '/collections', typesense.configuration.nodes[0]))
         .with(body: schema_for_creation,