chore: signer tests should wait for networking to come back up after 3.0 boundary

Author: kantai

testnet/stacks-node/src/tests/signer/v0.rs

@@ -264,6 +264,9 @@ impl SignerTest<SpawnedSigner> {
         info!("Signers initialized");
 
         self.run_until_epoch_3_boundary();
+        std::thread::sleep(Duration::from_secs(1));
+        wait_for(60, || Ok(get_chain_info_opt(&self.running_nodes.conf).is_some()))
+            .expect("Timed out waiting for network to restart after 3.0 boundary reached");
 
         // Wait until we see the first block of epoch 3.0.
         // Note, we don't use `nakamoto_blocks_mined` counter, because there