Use RawTable API in hash join code

[Dandandan]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
See the comment here.
#790 (comment)

It looks to me like both the performance and complexity of the hash join code can be improved when using the raw table API instead of.

Describe the solution you'd like
Rewrite the code to use the RawTable api. This should simplify the code and open up some opportunities to improve performance (faster collision checks(?)).

https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=9157e7ae2ad4d84f8bd6c358c42722cb

Describe alternatives you've considered
Custom hashmap implementation. It seems to me that using the hashbrown API might result in less code and might be more performant in some cases.

Additional context