fix(prover): Fix initial prover migration (#1083)

IF NOT EXISTS was missing for 1 index.
This causes migrations on already existing environments (testnet,
boojnet, mainnet) not to work. This PR addresses the miss.

prover/prover_dal/migrations/20240131134938_initial-prover-migration.up.sql

@@ -91,7 +91,6 @@ CREATE INDEX IF NOT EXISTS idx_leaf_aggregation_fri_status_processing_attempts
 
 ---- NODE AGGREGATION WITNESS JOBS FRI
 
--- Node aggregation jobs. Each is picked by a WG which produces input for provers.
 CREATE TABLE IF NOT EXISTS node_aggregation_witness_jobs_fri (
     id                       BIGSERIAL PRIMARY KEY,
     l1_batch_number          BIGINT NOT NULL,
@@ -179,7 +178,7 @@ COMMENT ON TABLE prover_jobs_fri IS 'Prover jobs. Each is picked by a WVG and is
 CREATE INDEX IF NOT EXISTS idx_prover_jobs_fri_circuit_id_agg_batch_num
     ON prover_jobs_fri (circuit_id, aggregation_round, l1_batch_number)
     WHERE (status = ANY (ARRAY['queued'::text, 'in_progress'::text, 'in_gpu_proof'::text, 'failed'::text]));
-CREATE INDEX idx_prover_jobs_fri_queued_order
+CREATE INDEX IF NOT EXISTS idx_prover_jobs_fri_queued_order
     ON prover_jobs_fri (aggregation_round DESC, l1_batch_number, id)
     WHERE (status = 'queued'::text);
 CREATE INDEX IF NOT EXISTS idx_prover_jobs_fri_queued_order2