message: common: remove TODO comments
  We decided to stick with error code IE013 for signaling batch stake
  insufficiency. Also, we will tackle gasLimits on a new PR.
diff: @@ -1180,7 +1180,7 @@ export class AllocationManager {
  if (newBalance.isNegative()) {
  {
  throw indexerError(
  - IndexerErrorCode.IE013, // TODO: Should we create a new error code?
  + IndexerErrorCode.IE013,
  `Unfeasible action batch: Approved action batch GRT balance is ` +
  `${formatGRT(batchDelta)} ` +
  `but available stake equals ${formatGRT(freeStake)}.`,
  @@ -1188,8 +1188,6 @@ export class AllocationManager {
  }
  }
  - // TODO: checkGasLimit(batch)
  -
  /* Return actions sorted by GRT balance (ascending).
  * This ensures on-chain batch feasibility because higher unallocations are processed
  * first and larger allocations are processed last */
  