Corrections to DB analyser tutorial in `ouroboros-consensus-cardano/README.md` #4755

Job	Run time
Build and test (8.10.7, default, all)	37m 18s
Build and test (9.6.6, default, all)	25m 14s
Build and test (9.10.1, default, all)	24m 26s
Run benchmarks (8.10.7)	30s
Deploy documentation to GitHub Pages	0s
Run benchmarks (9.6.6)	19s
Run benchmarks (9.10.1)	20s
	1h 28m 7s

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