cleanup(ooniprobe): remove unused send_crash_report option (#578)

Closes https://github.com/ooni/probe/issues/1766

cmd/ooniprobe/internal/config/settings.go

@@ -6,9 +6,7 @@ type Sharing struct {
 }
 
 // Advanced settings
-type Advanced struct {
-	SendCrashReports bool `json:"send_crash_reports"`
-}
+type Advanced struct{}
 
 // Nettests related settings
 type Nettests struct {

cmd/ooniprobe/internal/config/testdata/valid-config.json

@@ -8,6 +8,5 @@
     "websites_max_runtime": 0
   },
   "advanced": {
-    "send_crash_reports": true
   }
 }