Add BRAM numbers to resource estimate executive summary

[polybeandip]

Closes #2288

I've checked that this grabs the correct values. Say our main_utilization_placed.rpt file had the following BRAM table

(not a real utilization file, I changed the highlighted entry from 0 to 9 to make sure I'm grabbing the correct value)

Running fud e --from synth-files --to resource-estimate report yields the correct BRAM count of 9:

{
  "lut": 169,
  "dsp": 0,
  "brams": 9,
  "registers": 60,
  "muxes": 30,
  "clb_registers": 210,
  "carry8": 10,
  "f7_muxes": 0,
  "f8_muxes": 0,
  "f9_muxes": 0,
  "clb": 389,
  "meet_timing": 1,
  "worst_slack": 4.758,
  "period": 7.0,
  "frequency": 142.857,
  "uram": -1,
  "cell_lut1": 5,
  "cell_lut2": 110,
  "cell_lut3": 38,
  "cell_lut4": 17,
  "cell_lut5": 18,
  "cell_lut6": 49,
  "cell_fdre": 210
}

[rachitnigam]

Let's merge #2356 first which is a more substantial rework of the extraction logic.