Failed to reprocess job

Hi,

i have a weird issue rerunning a job. (I wanted to rerun a PDF, that wasn't properly processed with an OCR-layer).
When triggering the job, i saw that the job became stuck and the joex tried to rerun the job two times until it failed.

Looking into the docker logs if the joex i saw, that there was the following error:

```
doobie.util.invariant$NonNullableColumnRead: SQL `NULL` read at column 1 (JDBC type Char) but mapping is to a non-Option type; use Option here. Note that JDBC column indexing is 1-based.
```

It seems to me like some sort of DB-issue.

I'm currently running the docspell version 0.43. I'm using a quite old version of postgres - could this be the issue?

```sql
SELECT version();
```

returns

```
PostgreSQL 11.16 (Debian 11.16-1.pgdg90+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, 64-bit
```