Fix crash when an invalid URI is parsed and error handling is attempted

When you pass in a payload with an invalid URI in a build with assertions enabled, it will crash.
Consuming the error from the failed URI parse prevents the error.

The crash is caused by the [llvm::expected](https://llvm.org/doxygen/classllvm_1_1Expected.html) having protection around trying to deconstruct without consuming the error first.

Reviewed By: kadircet

Differential Revision: https://reviews.llvm.org/D99872