[client] increase gRPC health check timeout to 5s

Bump the IsHealthy() context timeout from 1s to 5s for both the
management and signal gRPC clients to reduce false negatives on
slower or congested connections.

shared/management/client/grpc.go

@@ -30,6 +30,8 @@ import (
 
 const ConnectTimeout = 10 * time.Second
 
+const healthCheckTimeout = 5 * time.Second
+
 const (
 	// EnvMaxRecvMsgSize overrides the default gRPC max receive message size (4 MB)
 	// for the management client connection. Value is in bytes.
@@ -532,7 +534,7 @@ func (c *GrpcClient) IsHealthy() bool {
 	case connectivity.Ready:
 	}
 
-	ctx, cancel := context.WithTimeout(c.ctx, 1*time.Second)
+	ctx, cancel := context.WithTimeout(c.ctx, healthCheckTimeout)
 	defer cancel()
 
 	_, err := c.realClient.GetServerKey(ctx, &proto.Empty{})