fix: example config (#379)

Author: ltitanb

config.example.toml

@@ -61,6 +61,9 @@ http_timeout_seconds = 10
 # Maximum number of retries for validator registrations per relay
 # OPTIONAL, DEFAULT: 3
 register_validator_retry_limit = 3
+# Maximum number of validators to register in a single request.
+# OPTIONAL, DEFAULT: "" (unlimited)
+validator_registration_batch_size = ""
 
 # The PBS module needs one or more [[relays]] as defined below.
 [[relays]]
@@ -102,9 +105,6 @@ target_first_request_ms = 200
 # Frequency in ms to send get_header requests
 # OPTIONAL
 frequency_get_header_ms = 300
-# Maximum number of validators to register in a single request.
-# OPTIONAL, DEFAULT: "" (unlimited)
-validator_registration_batch_size = ""
 
 # Configuration for the PBS multiplexers, which enable different configs to be used for get header requests, depending on validator pubkey
 # Note that: