Prevent exception if no detailed_linter_results are available

app/models/linter_check_run.rb

@@ -6,7 +6,7 @@ class LinterCheckRun < ApplicationRecord
   belongs_to :file, class_name: 'CodeOcean::File'
 
   def self.create_from(testrun, assessment)
-    assessment[:detailed_linter_results].each do |linter_result|
+    assessment[:detailed_linter_results]&.each do |linter_result|
       check = LinterCheck.find_or_create_by!(code: linter_result[:code]) do |new_check|
         new_check.name = linter_result[:name]
         new_check.severity = linter_result[:severity]

lib/py_lint_adapter.rb

@@ -44,6 +44,8 @@ class PyLintAdapter < TestingFrameworkAdapter
     # The message will be translated once the results were stored in the database
     # See SubmissionScoring for actual function call
 
+    return assessment unless assessment[:detailed_linter_results].present?
+
     assessment[:detailed_linter_results].map! do |message|
       severity = message[:severity]
       name = message[:name]