Stacked on top of the CommandFailed retry fix (SERVER-127065).

`blockUntilIndexQueryable` sends `_shardsvrRunSearchIndexCommand` to each
shard with a 60 s `kRemoteCommandTimeout`. On slow aubsan builds the shard
can exceed that deadline, returning `NetworkInterfaceExceededTimeLimit`
(code 89) at the network layer. `Shard::shouldErrorBePropagated(89)` returns
`false` (hardcoded exclusion), so the old code wrapped the error in
`OperationFailed` and threw immediately — causing a spurious BF
(`search_meta_explain.js` in BF-43358) instead of retrying.

*Fix*: when `!shouldErrorBePropagated`, log and retry with `kRetryPeriodMs`
rather than throwing. This covers `NetworkInterfaceExceededTimeLimit` and all
other mongos-retriable network errors that might transiently fail the poll.

*File changed*: `src/mongo/db/query/search/search_index_command_testing_helper.h`