sdk: fix `RelayPoolNotification::Event` not sent #1131

Job	Run time
Build no_std (nightly)	1m 28s
Build (stable, -p nostr-sdk --features rocksdb)	36m 49s
Build FFI (stable, -p nostr-ffi)	26s
Build (1.66.0, -p nostr-sdk --features rocksdb)	4m 44s
Build (stable, -p nostr)	2m 0s
Build FFI (stable, -p nostr-sdk-ffi)	1m 29s
Build (stable, -p nostr --no-default-features --features alloc)	20s
Build WASM (stable, -p nostr)	19s
Build (stable, -p nostr --no-default-features --features "alloc all-nips")	54s
Build WASM (stable, -p nostr-sdk)	47s
Format	10s
Build (stable, -p nostr --features blocking)	2m 37s
Build WASM (stable, -p nostr-sdk --features indexeddb)	50s
Build (stable, -p nostr-database -p nostr-sdk)	3m 35s
Build WASM (stable, -p nostr-js)	17s
Build (stable, -p nostr-sdk --no-default-features)	1m 4s
Build WASM (1.64.0, -p nostr)	4m 34s
Build (stable, -p nostr-sdk --features blocking)	1m 46s
Build WASM (1.64.0, -p nostr-sdk)	4m 40s
Build (stable, -p nostr-sdk --features sqlite)	3m 28s
Build WASM (1.64.0, -p nostr-sdk --features indexeddb)	8m 35s
Build (1.64.0, -p nostr)	5m 18s
Build WASM (1.64.0, -p nostr-js)	4m 44s
Build (1.64.0, -p nostr --no-default-features --features alloc)	4m 43s
Build (1.64.0, -p nostr --no-default-features --features "alloc all-nips")	5m 3s
Build (1.64.0, -p nostr --features blocking)	10m 2s
Build (1.64.0, -p nostr-database -p nostr-sdk)	10m 49s
Build (1.64.0, -p nostr-sdk --no-default-features)	8m 47s
Build (1.64.0, -p nostr-sdk --features blocking)	5m 42s
Build (1.64.0, -p nostr-sdk --features sqlite)	6m 21s
	2h 22m 21s

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