Trigger an end-to-end check results in failure [1] even though the actual loading is fine [2].
And the report ui reports some traceback [3] that's nowhere to be found in the actual loader output [2]
```
06:05 <+swhbot> icinga PROBLEM: service production Check save-code-now panda with type svn end-to-end on pergamon.softwareheritage.org is CRITICAL: SAVECODENOW CRITICAL - Save code now request for origin ('svn', 'https://subversion.renater.fr/anonscm/svn/panda') took 11.53s and failed.
```
[2]
```
Feb 02 08:22:07 worker09 python3[753971]: [2022-02-02 08:22:07,282: INFO/ForkPoolWorker-103] Load origin 'https://subversion.renater.fr/anonscm/svn/panda' with type 'svn'
Feb 02 08:22:11 worker09 python3[753971]: [2022-02-02 08:22:11,305: WARNING/ForkPoolWorker-103] Retrying RPC call
Feb 02 08:22:15 worker09 python3[753971]: [2022-02-02 08:22:15,543: WARNING/ForkPoolWorker-103] Retrying RPC call
Feb 02 08:22:21 worker09 python3[753971]: [2022-02-02 08:22:21,054: WARNING/ForkPoolWorker-103] Retrying RPC call
Feb 02 08:22:27 worker09 python3[753971]: [2022-02-02 08:22:27,724: WARNING/ForkPoolWorker-103] file:///tmp/swh.loader.svn.ughfe6v8-753971/swh.loader.svn.prjkpn10-753971/tmp7b0fozij@5 already injected.
Feb 02 08:22:27 worker09 python3[753971]: [2022-02-02 08:22:27,925: INFO/ForkPoolWorker-103] Task swh.loader.svn.tasks.DumpMountAndLoadSvnRepository[8c7d82e3-68fd-41e6-9239-f6f24262e307] succeeded in 20.700052144005895s: {'status': 'uneventful'}
```
[3]
```
Traceback (most recent call last):
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request
Reason: Error reading from remote server
```
Sentry issue: https://sentry.softwareheritage.org/share/issue/aa281f3b760348e6b79708ce3c93a32d/