Deprecate DisableLegacyLimitWrites & UseKvLimitsForNewOrder flags; remove code using certificatesPerName & newOrdersRL tables #7526

Job	Run time
govulncheck	15s
b (go1.23.1_2024-09-05, ./t.sh --lints --generate)	3m 30s
vendorcheck (1.22.5)	26s
b (go1.23.1_2024-09-05, ./t.sh --integration)	5m 41s
b (go1.23.1_2024-09-05, ./tn.sh --integration)	7m 57s
b (go1.23.1_2024-09-05, ./t.sh --unit --enable-race-detection)	7m 43s
b (go1.23.1_2024-09-05, ./tn.sh --unit --enable-race-detection)	7m 47s
b (go1.23.1_2024-09-05, ./t.sh --start-py)	2m 52s
Boulder CI Test Matrix	1s
	36m 12s

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