Server crash when using the referential integrity plugin(referint.c)

[iamarty3z]

Issue Description
Server crash when using the referential integrity plugin when transactions are used and an error occurs when opening a file for writing

Steps to Reproduce
Steps to reproduce the behavior:

1. enable the plugin using transactions (betxnpostoperation)
2. set delay > =1
3. remove permission to write to the directory where the log file will be created
4. move entry from containerscope
5. server crash

Expected results
Logging an error message and continuing work

Additional context
The crash is caused by using an uninitialized mutex PR_Unlock(referint_mutex)) after the error message and before calling referint_unlock();

[progier389]

closing as duplicate of #6166