Apply suggestions from code review

Author: jheysel-r7

modules/exploits/multi/http/atlassian_confluence_rce_cve_2024_21683.rb

@@ -155,7 +155,7 @@ def get_csrf(page, operation)
 
     vprint_status("Grabbed #{operation} CSRF token: #{csrf_token}")
 
-    return csrf_token
+    csrf_token
   end
 
   def get_host_os
@@ -177,7 +177,7 @@ def get_host_os
     vprint_status("Target returned the operating system string '#{os}'")
 
     # If the string begins with "win", assume the host is Windows. If it's anything else, assume it's something Unix-based.
-    return os.downcase.start_with?('win') ? 'win' : 'nix'
+    os.downcase.start_with?('win') ? 'win' : 'nix'
   end
 
   def upload_payload(shell)
@@ -208,10 +208,10 @@ def upload_payload(shell)
     )
 
     # Connection failure, no response, or malformed response.
-    fail_with(Failure::Unknown, 'Target did not respond as expected during code execution attempt') unless res_upload
+    print_error('Target did not respond as expected during code execution attempt') unless res_upload
 
     # If the response to the multipart request does not return a 200.
-    print_error(Failure::Unknown, 'The application returned a non-200 response during code execution attempt') unless res_upload.code == 200
+    print_error('The application returned a non-200 response during code execution attempt') unless res_upload.code == 200
   end
 
   def exploit