fix: previously broken specs

In #19 we changed the default version
but we never updated the specs accordingly.

spec/netsuite/configuration_spec.rb

@@ -56,7 +56,7 @@
 
     context 'when the wsdl has not been set' do
       it 'returns a path to the WSDL to use for the API' do
-        expect(config.wsdl).to eq("https://webservices.netsuite.com/wsdl/v2015_1_0/netsuite.wsdl")
+        expect(config.wsdl).to eq("https://webservices.netsuite.com/wsdl/v2023_1_0/netsuite.wsdl")
       end
     end
 
@@ -290,7 +290,7 @@
   describe '#api_version' do
     context 'when no api_version is defined' do
       it 'defaults to 2015_1' do
-        expect(config.api_version).to eq('2015_1')
+        expect(config.api_version).to eq('2023_1')
       end
     end
   end