Don't raise a type error on assoc patterns

[PuercoPop]

This is a fix for #54, There are still a couple of issues that I'm unsure of how to best address.

• Whether to use handler-case or handler-bind should be used
• The handler-* approach introduces a potential issue. It will 'hide' type-errors raised by a key function (if they happen)
• This incompatibilty no longer signals a type-error (nor does it appear to match the commented test-case

Note: I pushed the pr branch to the main repo instead of my fork so you could commit to it if you want to

[guicho271828]

still vulnerable to cases where errors occur multiple times, restart is also called multiple times etc.

[guicho271828]

the initial study was very helpful, it revealed the important points that I should be aware of. thank you so much!