Uploaded files: any file of the upload directory given as input is deleted, also before a retry #228

Regression of 3.4 (#209).

UploadedFileManager::deleteInput() deletes any input that is a file directly in upload_directory, not only the files the bundle has just written (the comment "never a file given by its path" is wrong):

• an API user (ROLE_USER + token) sending input=/…/uploads/<file of another user> deletes it, e.g. a file still waiting in the asynchronous queue, whose execution then fails; the same with the launch form when entrypoint_type is text;
• a ProcessSchedule (or a ui.default.input) whose input is a reference file of this directory loses it after its first execution.

Also, the input is deleted in a finally, so when the execution fails too: when the application configures retries (retry_strategy, failure_transport, messenger:failed:retry), the retried message runs without its file.

And a file written by HttpProcessExecuteValueResolver is never deleted when the request is rejected by the validation (422).

Fix:

• an explicit flag in ProcessExecuteMessage (and for the synchronous HTTP execution), set only by LaunchAction and HttpProcessExecuteValueResolver for the file they have just written; never decide from the path only;
• in the Messenger handler path, keep the file while the message will be retried;
• delete the written file on a 422.

Found during the audit after the 3.4 release (audit-v4-post-release.md #216, #221, #222).