Replace MAX_BLOB_EPOCHS usages with more accurate terms (#13098)

Co-authored-by: terencechain <[email protected]>
Co-authored-by: Nishant Das <[email protected]>

beacon-chain/db/kv/blob.go

@@ -48,7 +48,7 @@ func (rk blobRotatingKey) BlockRoot() []byte {
 
 // SaveBlobSidecar saves the blobs for a given epoch in the sidecar bucket. When we receive a blob:
 //
-//  1. Convert slot using a modulo operator to [0, maxSlots] where maxSlots = MAX_BLOB_EPOCHS*SLOTS_PER_EPOCH
+//  1. Convert slot using a modulo operator to [0, maxSlots] where maxSlots = MAX_EPOCHS_TO_PERSIST_BLOBS*SLOTS_PER_EPOCH
 //
 //  2. Compute key for blob as bytes(slot_to_rotating_buffer(blob.slot)) ++ bytes(blob.slot) ++ blob.block_root
 //
@@ -121,7 +121,8 @@ func (s *Store) SaveBlobSidecar(ctx context.Context, scs []*ethpb.BlobSidecar) e
 	})
 }
 
-// validUniqueSidecars ensures that all sidecars have the same slot, parent root, block root, and proposer index, and no more than MAX_BLOB_EPOCHS.
+// validUniqueSidecars ensures that all sidecars have the same slot, parent root, block root, and proposer index, and
+// there are no more than MAX_BLOBS_PER_BLOCK sidecars.
 func validUniqueSidecars(scs []*ethpb.BlobSidecar) ([]*ethpb.BlobSidecar, error) {
 	if len(scs) == 0 {
 		return nil, errEmptySidecar