Auto merge of #113303 - compiler-errors:yeet-chalk, r=lcnr

Remove chalk support from the compiler

Removes chalk (`-Ztrait-solver=chalk`) from the compiler and prunes any dead code resulting from this, mainly:
* Remove the chalk compatibility layer in `compiler/rustc_traits/src/chalk`
* Remove the chalk flag `-Ztrait-solver=chalk` and its `TraitEngine` implementation
* Remove `TypeWellFormedFromEnv` (and its many `bug!()` match arms)
* Remove the chalk migration mode from compiletest
* Remove the `chalkify` UI tests (do we want to keep any of these, but migrate them to `-Ztrait-solver=next`??)

Fulfills rust-lang/types-team#93.

r? `@jackh726`

compiler/rustc_lint/src/builtin.rs

@@ -1606,8 +1606,7 @@ impl<'tcx> LateLintPass<'tcx> for TrivialConstraints {
                     // Ignore bounds that a user can't type
                     | ClauseKind::WellFormed(..)
                     // FIXME(generic_const_exprs): `ConstEvaluatable` can be written
-                    | ClauseKind::ConstEvaluatable(..)
-                    | ClauseKind::TypeWellFormedFromEnv(_)  => continue,
+                    | ClauseKind::ConstEvaluatable(..)  => continue,
                 };
                 if predicate.is_global() {
                     cx.emit_spanned_lint(