multi: Add itest for funding timeout

This commit adds an integration test that
verifies the funding timeout behavior in the
funding manager, in dev/integration test.
Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>

lncfg/dev.go

@@ -46,3 +46,9 @@ func (d *DevConfig) GetReservationTimeout() time.Duration {
 func (d *DevConfig) GetZombieSweeperInterval() time.Duration {
 	return DefaultZombieSweeperInterval
 }
+
+// GetMaxWaitNumBlocksFundingConf returns the config value for
+// `MaxWaitNumBlocksFundingConf`.
+func (d *DevConfig) GetMaxWaitNumBlocksFundingConf() uint32 {
+	return DefaultMaxWaitNumBlocksFundingConf
+}