Fix changelog after d2af2263
Fix changelog after d2af2263

d2af2263c71fb836201346dd798a2cec6e67f27b had to roll back the impl of `AsExpression<Nullable<sql_types::Bool>>` for `E: AsExpression<sql_types::Bool>`, to allow for more type inference, but forgot to remove the corresponding line in the changelog.

sgrif/diesel,diesel-rs/diesel,diesel-rs/diesel,sgrif/diesel