Bug#851147: --max-report-size does not apply to --text reports

[Hans-Christoph Steiner]

Package: diffoscope
Version: 67

On https://verification.fdroid.org, diffoscope is run like this:

diffoscope --max-report-size 12345678 --max-diff-block-lines 100 \
  --html foo.html  --text bar.txt

The HTML reports are being size-limited, but there are still some giant
text reports, including a few that are hundreds of MB:

https://verification.f-droid.org/?C=S;O=D