fix: ToDevice transport not setting the sent_ts

Author: BillCarsonFr

spec/unit/matrixrtc/ToDeviceKeyTransport.spec.ts

@@ -101,6 +101,7 @@ describe("ToDeviceKeyTransport", () => {
                     call_id: "",
                     scope: "m.room",
                 },
+                sent_ts: expect.any(Number),
             },
         );
 

src/matrixrtc/ToDeviceKeyTransport.ts

@@ -68,6 +68,7 @@ export class ToDeviceKeyTransport
                 application: "m.call",
                 scope: "m.room",
             },
+            sent_ts: Date.now(),
         };
 
         const targets = members