debian.loader: Overcome wrong size download information provided

• loader has bad information input (size)
• We check for download size with that incorrect data.
• download call function fails because it checks the local size and it's difference

So this opens a flag to bypass that error (only activated for debian). the loader will still check the provided hashes. If they are also wrong then we cannot do anything else (from the code standpoint).

That occurrence [1] happens a lot... already 1.1k since i restarted the debian loader... (less than 1 hour ago or so).

I've checked manually and downloaded files are correct regarding hashes. Note that it seems to happen mostly for the asc files... not the other ones.

• [1] https://sentry.softwareheritage.org/share/issue/49d464bee7b24ad080598b32cd3eb9a8/

• [2] https://sentry.softwareheritage.org/organizations/swh/issues/?project=9&query=is%3Aunresolved&sort=freq&statsPeriod=14d

Test Plan

tox

---

Migrated from D2485 (view on Phabricator)