bitswap: mark TestSessionGetBlocks flaky

https://github.com/ipfs/boxo/actions/runs/5975685205/job/16212124664?pr=422

Author: Jorropo

bitswap/client/internal/session/session_test.go

@@ -149,6 +149,8 @@ func (pm *fakePeerManager) BroadcastWantHaves(ctx context.Context, cids []cid.Ci
 func (pm *fakePeerManager) SendCancels(ctx context.Context, cancels []cid.Cid) {}
 
 func TestSessionGetBlocks(t *testing.T) {
+	test.Flaky(t)
+
 	ctx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
 	fpm := newFakePeerManager()
 	fspm := newFakeSessionPeerManager()