[Rewrite Synthesis] Fix args for non-chaining ops (#7996)

[Rewrite Synthesis] Fix args for non-chaining ops (#7996)

Fixes https://github.com/cvc5/cvc5-projects/issues/445. Fixes
https://github.com/cvc5/cvc5-projects/issues/446. The issue is related
to the preprocessing pass for doing rewrite rule synthesis based on the
input. It was removing duplicate arguments from both chaining operators
and non-chaining operators when constructing the corresponding
datatypes. In the case of non-chaining operators, it could happen that
the constructor of the datatype did not have the correct number of
arguments for a given kind if there was a term where multiple arguments
were the same. This commit fixes the issue by doing the duplicate
elimination only for chaining operators.