accdb: fix overlapping bitmask value

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No description provided.

[github-actions]

Performance Measurements ⏳

Suite	Baseline	New	Change
backtest mainnet-368528500-perf per slot	0.070242 s	0.07021 s	-0.046% ✅
backtest mainnet-368528500-perf snapshot load	NaN s	NaN s	NaN% ✅
backtest mainnet-368528500-perf total elapsed	70.241561 s	70.210481 s	-0.044% ✅
firedancer mem usage with mainnet.toml	NaN GiB	NaN GiB	NaN% ✅

[ripatel-fd]

Thank you

[github-actions]

Performance Measurements ⏳

Suite	Baseline	New	Change
backtest mainnet-368528500-perf per slot	0.051635 s	0.052008 s	0.722% ✅
backtest mainnet-368528500-perf snapshot load	NaN s	NaN s	NaN% ✅
backtest mainnet-368528500-perf total elapsed	51.635374 s	52.007824 s	0.721% ✅
firedancer mem usage with mainnet.toml	1058.31 GiB	1058.31 GiB	0.000% ✅