Fix for errors without line numbers

[Sentry changed IPs](https://status.sentry.io/incidents/qmh29yyv8bbv)
and this caused problems with client report sending.

The current problem is that client report sending is stuck in a loop if
the client report itself cannot be sent:
`Event fails → Client Report #1 fails → Client Report #2 fails → Client
Report #3 fails → ∞`

With this fix, failed client reports are not sent anymore to prevent
this infinite feedback loop.

The offline transport already drops client reports when they cannot be
sent:

https://github.com/getsentry/sentry-javascript/blob/1b41126666e27a311884cf6f7c1ef915f95477de/packages/core/src/transports/offline.ts#L83-L86


I tested this locally by adding an entry to `/etc/hosts`: `0.0.0.0
o1.ingest.sentry.io` (the example in the issue below)

Closes #18802