[Clang][Sema] Do not evaluate value-dependent immediate invocations

Value-dependent ConstantExprs are not meant to be evaluated.
There is an assert in Expr::EvaluateAsConstantExpr that ensures this condition.
But before this patch the method was called without prior check.

Fixes https://github.com/llvm/llvm-project/issues/52768

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D119375