hir_analysis: add missing sizedness bounds
Depends on rust-lang/rust#144064
Default sizedness bounds were not being added to `explicit_super_predicates_of` and `explicit_implied_predicates_of` which meant that a trait bound added to a associated type projection would be missing the implied predicate of the default sizedness supertrait of that trait.
An unexpected consequence of this change was that the check for multiple principals was now finding an additional `MetaSized` principal when eagerly expanding trait aliases - which is fixed by skipping `MetaSized` when elaborating trait aliases in lowering `dyn TraitAlias`.
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