USE_V1_PUBLISH_BLOCK_ENDPOINT flag works the wrong way around

[alextes]

The flag appears to use the publish exactly the wrong way around.

if c.ffUseV1PublishBlockEndpoint {                                                                   
	uri = fmt.Sprintf("%s/eth/v2/beacon/blocks?broadcast_validation=%s", c.beaconURI, broadcastMode) 
} else {                                                                                             
	uri = fmt.Sprintf("%s/eth/v1/beacon/blocks", c.beaconURI)                                        
}                                                                                                    

mev-boost-relay/beaconclient/prod_beacon_instance.go

Line 246 in d8a0d7b

if c.ffUseV1PublishBlockEndpoint {

[avalonche]

Resolved as part of #585. Thank you for raising this!