use grpc abci protocol in e2e tests (#6652)

test/e2e/generator/generate.go

@@ -28,9 +28,8 @@ var (
 	}
 
 	// The following specify randomly chosen values for testnet nodes.
-	nodeDatabases = uniformChoice{"goleveldb", "cleveldb", "rocksdb", "boltdb", "badgerdb"}
-	// FIXME: grpc disabled due to https://github.com/tendermint/tendermint/issues/5439
-	nodeABCIProtocols    = uniformChoice{"unix", "tcp", "builtin"} // "grpc"
+	nodeDatabases        = uniformChoice{"goleveldb", "cleveldb", "rocksdb", "boltdb", "badgerdb"}
+	nodeABCIProtocols    = uniformChoice{"unix", "tcp", "builtin", "grpc"}
 	nodePrivvalProtocols = uniformChoice{"file", "unix", "tcp", "grpc"}
 	// FIXME: v2 disabled due to flake
 	nodeFastSyncs         = uniformChoice{"v0"} // "v2"

test/e2e/networks/ci.toml

@@ -52,8 +52,7 @@ seeds = ["seed02"]
 [node.validator03]
 database = "badgerdb"
 seeds = ["seed01"]
-# FIXME: should be grpc, disabled due to https://github.com/tendermint/tendermint/issues/5439
-#abci_protocol = "grpc"
+abci_protocol = "grpc"
 persist_interval = 3
 perturb = ["kill"]
 privval_protocol = "grpc"
@@ -70,8 +69,7 @@ database = "cleveldb"
 fast_sync = "v0" 
 seeds = ["seed02"] 
 start_at = 1005 # Becomes part of the validator set at 1010
-# FIXME: should be grpc, disabled due to https://github.com/tendermint/tendermint/issues/5439
-#abci_protocol = "grpc"
+abci_protocol = "grpc"
 perturb = ["kill", "pause", "disconnect", "restart"]
 privval_protocol = "tcp"