Broadcast uncle blocks at the same height

To reduce orphan block rate

src/side_chain.cpp

@@ -1662,6 +1662,10 @@ void SideChain::update_chain_tip(const PoolBlock* block)
 		LOGINFO(4, "possible uncle block: id = " << log::Gray() << block->m_sidechainId << log::NoColor() <<
 			", height = " << log::Gray() << block->m_sidechainHeight);
 		m_pool->update_block_template_async();
+		// Broadcast it if it's at the same height to give it higher chances to be mined
+		if (block->m_sidechainHeight == tip->m_sidechainHeight) {
+			block->m_wantBroadcast = true;
+		}
 	}
 
 	if (p2pServer() && block->m_wantBroadcast && !block->m_broadcasted) {