Auto merge of #122684 - oli-obk:delay_interning_errors_to_after_valid…

…aiton, r=RalfJung

Delay interning errors to after validation

fixes rust-lang/rust#122398
fixes #122548

This improves diagnostics since validation errors are usually more helpful compared with interning errors that just make broad statements about the entire constant

r? `@RalfJung`