Created attachment 839952 [details]
Description of problem:
When a user attempts to generate a process PDF more than once then every time he tries an exception will end up in the server log. See attached stack-trace.
Steps to Reproduce:
1. Create a process
2. Download PDF (at least twice)
Exception in the server log.
No exception in server log.
Fixed on master
Process PDF can be downloaded multiple times
Verified on 6.3.0.DR1