fix: harness tests random panic (#10933)

* fix: harness tests random panic

Connecting nodes in parallel can cause TLS handshake failures. For each node, connect to the other nodes serially. It is not necessary to connect in parallel as it does not save any significant time.

Closes #10932

Author: gammazero

test/cli/harness/nodes.go

@@ -5,7 +5,6 @@ import (
 
 	. "github.com/ipfs/kubo/test/cli/testutils"
 	"github.com/multiformats/go-multiaddr"
-	"golang.org/x/sync/errgroup"
 )
 
 // Nodes is a collection of Kubo nodes along with operations on groups of nodes.
@@ -17,37 +16,28 @@ func (n Nodes) Init(args ...string) Nodes {
 }
 
 func (n Nodes) ForEachPar(f func(*Node)) {
-	group := &errgroup.Group{}
+	var wg sync.WaitGroup
 	for _, node := range n {
+		wg.Add(1)
 		node := node
-		group.Go(func() error {
+		go func() {
+			defer wg.Done()
 			f(node)
-			return nil
-		})
-	}
-	err := group.Wait()
-	if err != nil {
-		panic(err)
+		}()
 	}
+	wg.Wait()
 }
 
 func (n Nodes) Connect() Nodes {
-	wg := sync.WaitGroup{}
 	for i, node := range n {
 		for j, otherNode := range n {
 			if i == j {
 				continue
 			}
-			node := node
-			otherNode := otherNode
-			wg.Add(1)
-			go func() {
-				defer wg.Done()
-				node.Connect(otherNode)
-			}()
+			// Do not connect in parallel, because that can cause TLS handshake problems on some platforms.
+			node.Connect(otherNode)
 		}
 	}
-	wg.Wait()
 	for _, node := range n {
 		firstPeer := node.Peers()[0]
 		if _, err := firstPeer.ValueForProtocol(multiaddr.P_P2P); err != nil {