fix: bitswap check err.name in peer-want-lists/ledger

[dozyio]

Description

Was hitting a weird edge case where err.code is not set. Adding an additional check for err.name fixes the issue.

I was only hitting the edge case with 3+ nodes using MemoryDatastore, 2 nodes seemed fine.

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation if necessary (this includes comments as well)
• I have added tests that prove my fix is effective or that my feature works

[dozyio]

Not sure if you want to close this PR - didn't see #585 when I stated debugging

[achingbrain]

Thanks for opening this - it's been fixed upstream by ipfs/js-stores#320 so the breakage should be over now.