Rollup merge of #133779 - BoxyUwU:array_const_arg_infer_hir_id, r=compiler-errors

Use correct `hir_id` for array const arg infers

Fixes #133771

`self.next_id()` results in the `DefId` for the const argument, created from the hack introduced by #133468, having no `HirId` associated with it. This then results in an ICE in metadata encoding. Fixing this then results in *another* ICE where `encode_defs` was not skipping encoding `type_of` and other queries for `DefId`s when they correspond to a `ConstArgKind::Infer` node.

This only reproduces with a library crate as metadata is not encoded for binaries, and apparently we had 0 tests for `generic_arg_infer` for array lengths in a library crate so this was not caught :<

cc #133589 `@voidc`

r? `@compiler-errors` `@lcnr`

Author: matthiaskrgr