test: fix various E2E test issues (#5576)

* Don't use state sync for nodes starting at initial height.
* Also remove stopped containers when cleaning up.
* Start nodes in order of startAt, mode, name to avoid full nodes starting before their seeds.
* Tweak network waiting to avoid halts caused by validator changes and perturbations.
* Disable most tests for seed nodes, which aren't always able to join consensus.
* Disable `blockchain/v2` due to known bugs.

test/e2e/pkg/testnet.go

@@ -403,6 +403,16 @@ func (t Testnet) IPv6() bool {
 	return t.IP.IP.To4() == nil
 }
 
+// HasPerturbations returns whether the network has any perturbations.
+func (t Testnet) HasPerturbations() bool {
+	for _, node := range t.Nodes {
+		if len(node.Perturbations) > 0 {
+			return true
+		}
+	}
+	return false
+}
+
 // LastMisbehaviorHeight returns the height of the last misbehavior.
 func (t Testnet) LastMisbehaviorHeight() int64 {
 	lastHeight := int64(0)