[doc] Better explain HyperDebug flashing #5907

Job	Run time
Lint (quick)	3m 25s
Lint (slow)	11m 0s
Airgapped build	10m 51s
Build documentation	5m 22s
CW305's Bitstream	23m 21s
Run OTBN crypto tests	3m 1s
Run OTBN smoke Test	2m 49s
Verible lint	1m 9s
Verilated Earl Grey	1h 19m 47s
Verilated English Breakfast	8m 0s
Build Docker Containers	2m 26s
QEMU smoketest	1m 52s
Build and test software	15m 57s
Build and test Darjeeling software	3m 57s
Earl Grey for CW310 / Build bitstream	1h 4m 46s
Earl Grey for CW310 Hyperdebug / Build bitstream	1h 2m 49s
Earl Grey for CW340 / Build bitstream	1h 31m 0s
CW310 Manufacturing Tests / FPGA test	30m 16s
CW310 SiVal ROM_EXT Tests / FPGA test	31m 14s
Hyper310 ROM_EXT Tests / FPGA test	11m 31s
CW310 SiVal Tests / FPGA test	22m 23s
CW310 ROM Tests / FPGA test	38m 0s
CW310 Test ROM Tests / FPGA test	3m 16s
Cache bitstreams to GCP	0s
CW340 ROM_EXT Tests / FPGA test	4m 43s
CW340 Manufacturing Tests / FPGA test	39m 30s
CW340 Test ROM Tests / FPGA test	3m 22s
CW340 ROM Tests / FPGA test	46s
CW340 SiVal Tests / FPGA test	15m 56s
CW340 SiVal ROM_EXT Tests / FPGA test	3m 44s
Verify FPGA jobs	22s
	9h 56m 35s

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