Scoped disposal within an exception handler generates incorrect IL

[degory]

Attempting to declare scoped disposed variables with let use inside a try or catch block results in invalid IL that fails at runtime.

The root cause is that a ret IL instruction is emitted inside the outer exception handler, which is not not supported in CIL.

The rest of the post-finally return handling boilerplate is correctly emitted, but the ret needs to be replaced with a leave targeting the label immediately after the finally where the return handling code is.