fix: Verify supported type for Unary::Plus in sql planner

[eejbyfeldt]

Which issue does this PR close?

Closes #11175.

Rationale for this change

This makes datafusion reject unary plus in more cases. This aligns our behavior with postgres and other engines by rejecting sql like select +true.

What changes are included in this PR?

This adds a type check when planning unary plus operator. Since we currently do not represent the operator in our logical plan we can not check it later. Instead of introducing a new Expr this patch just verifies the type during the translation instead.

Are these changes tested?

New and existing tests.

Are there any user-facing changes?

We will no reject Unary::Plus in more cases. There is some risk that the old behavior hide bug in users code that no will cause failures.