Memory dump detection: dump file dropped because it's too big

The memory dump detection feature created an event, but no dump file was attached.

I was only able to find out what happened because the SDK logs are sent to google cloud logging. And I found it:

```
jsonPayload: {
0: "HttpTransport"
1: "20250227_072623_1.gcdump"
2: 161153506
@l: "Warning"
@mt: "{0}: Attachment '{1}' dropped because it's too large ({2} bytes)."
@t: "2025-02-27T07:26:46.1279762Z"
MachineName: "symbol-collector-6b45d484f7-7ks87"
SourceContext: "Sentry.ISentryClient"
}
```

[https://console.cloud.google.com/kubernetes/deployment/us-central1-b/zdpwkxst/default/symbol-collector/logs?invt=AbqtWg&project=internal-sentry&rapt=AEjHL4Pycm2CIGp9OPDNBq9dWM8XDAhfti7gFFXRZH1YB5BmzYneOn020lZbGvX-j61FjNflNHB1FM9rLFjC7pn0w6Y_z_hVX1BS-GN9h1MManAXE6IU3-8&inv=1]()

We could show something in the UI saying the dump file was too large.
Or we could avoid sending the event altogether. But this means now the server could crash OOM and we have no event in Sentry at all. Which is probably even worse.