Fix failing test

Version 3.13.2 of the rspec-expectations gems updates the `include` matcher to
raise an exception if no arguments are passed. See rspec/rspec-expectations#1479

The `expected_interim_fees_for` helper is meant to return an array of expected
options in a case type selection to be used in the `include` matcher. However,
in some cases `nil` is returned resulting in no arguments resulting in an
exception. This was masking failures as the test was checking that the list
included items in an empty array and was therefore always passing.

It turns out that an update to `govuk-form-builder` from some time ago changed
the id of select boxes and so the list of options being tested was always
empty. This should have immediately resulted in a a failure but it was missed
due to the bug in `expected_interim_fees_for`.

features/page_objects/sections/lgfs_interim_fee_section.rb

@@ -4,7 +4,7 @@ class SelectOptionSection < SitePrism::Section
 class LGFSInterimFeeSection < SitePrism::Section
   include SelectHelper
 
-  sections :fee_type_select_options, SelectOptionSection, 'select#claim_interim_fee_attributes_fee_type_id option', visible: false
+  sections :fee_type_select_options, SelectOptionSection, 'select#claim-interim-fee-attributes-fee-type-id-field option', visible: false
   element :select_container, '.fee-type select', visible: false
 
   # common interim fee fields

features/step_definitions/litigator_interim_claim_steps.rb

@@ -86,7 +86,8 @@
 end
 
 def expected_interim_fees_for(case_type_name)
-  expected = ['Disbursement only', 'Warrant']
-  expected += ['Effective PCMH', 'Trial start'] if case_type_name.casecmp('trial').eql?(0)
-  expected += ['Retrial start','Retrial new solicitor'] if case_type_name.casecmp('retrial').eql?(0)
+  return ['Disbursement only', 'Warrant', 'Effective PCMH', 'Trial start'] if case_type_name.casecmp('trial').eql?(0)
+  return ['Disbursement only', 'Warrant', 'Retrial start','Retrial new solicitor'] if case_type_name.casecmp('retrial').eql?(0)
+
+  ['Disbursement only', 'Warrant']
 end