chore(*): add mathlib4 synchronization comments (#19211)
Regenerated from the [port status wiki page](https://github.com/leanprover-community/mathlib/wiki/mathlib4-port-status).
Relates to the following files:
* `algebra.category.Group.adjunctions`
* `analysis.constant_speed`
* `analysis.convolution`
* `category_theory.category.PartialFun`
* `control.bitraversable.instances`
* `control.uliftable`
* `data.nat.nth`
* `field_theory.cardinality`
* `field_theory.finite.galois_field`
* `field_theory.finite.trace`
* `number_theory.function_field`
* `number_theory.number_field.basic`
* `number_theory.number_field.norm`
* `number_theory.prime_counting`
* `number_theory.zeta_values`
* `probability.ident_distrib`
* `probability.kernel.cond_distrib`
* `probability.kernel.condexp`
* `probability.moments`
* `probability.strong_law`
* `probability.variance`
* `representation_theory.Rep`
* `ring_theory.complex`
* `ring_theory.valuation.ramification_group`
* `ring_theory.valuation.valuation_subring`
* `set_theory.ordinal.notation`
