Bump pdfbox from 2.0.19 to 2.0.20
Bump pdfbox from 2.0.19 to 2.0.20

Bumps pdfbox from 2.0.19 to 2.0.20.

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
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