Move fuel consumption point to an earlier stage in the cudnn fused convolution rewriter
Move fuel consumption point to an earlier stage in the cudnn fused convolution rewriter

The call to `ConsumeFuel` happened after `EnsureIfConvBiasActivation` had already rewritten
the convolution instruction. In order to effectively use `ConsumeFuel` for model
bisection I'm moving the check to before any changes are made to the instruction.
