Dear Maintainer,

I noticed on salsa-ci that my package is not reproducible (according to the
reprotest job) because of the mangpage that is generated with pandoc from
Markdown.

The issue is in the header where the date is not correct
```
.\"·Automatically·generated·by·Pandoc·3.1.11.1
.\"
.TH·"vnu\-server"·"1"·"2025\-06\-08"·"vnu\-server·23.4.11+dfsg6"·""
```

2nd run:
```
.\"·Automatically·generated·by·Pandoc·3.1.11.1
.\"
.TH·"vnu\-server"·"1"·"2025\-06\-07"·"vnu\-server·23.4.11+dfsg6"·""
```

Date of package in changelog:

Sat, 07 Jun 2025 17:57:32 +0200

Command: The same in both cases.

for page in vnu vnu-client vnu-server; do \
  pandoc --standalone --from markdown -f markdown-smart --to man \
  -M title:"${page}(1) ${page} 23.4.11+dfsg6" \
  -M date:"$(date -d'@1749311852' +%Y-%m-%d)" docs/${page}.1.md >
docs/${page}.1 ; \
done