PDF-export ignores locale for date format

[RicardoDeden]

Describe the bug
When using the PDF-export, the headless browser ignores the host's locale settings and defaults to "en-US" for date formats.

To Reproduce
Steps to reproduce the behaviour:
Open report - press the "Download report as PDF" button.
Result: dates in the "About this report" section are formatted as "MM-DD-YYYY", regardless of your locale settings.

Expected behaviour
Date formatted according to host's locale settings, or according to the global settings for the renderer's container, which is "en-GB".

Screenshots

Your environment (please complete the following information):

• OS: macOS
• Browser: Chromium headless
• Quality-time version v5.9.0