Fix missing origin in permalink box when using old SWHID

When using an old SWHID with context:

https://archive.softwareheritage.org/swh:1:cnt:64582b78792cd6c2d67d35da5a11bb80886a6409;origin=https://github.com/virtualagc/virtualagc;lines=245-261/

The origin in the permalink box is missing. There is also an empty path:

swh:1:cnt:64582b78792cd6c2d67d35da5a11bb80886a6409;path=/;lines=245-261

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Migrated from T2427 (view on Phabricator)