update submodule with elimEta fix

[yiyunliu]

I did include a negative test file which returns exit code 1 for the fixed elimEta and 2 for the buggy one. However, I need to test Wen's example before this can be safely merged.

[yiyunliu]

For some reason circleci didn't checkout the updated submodule..

[nikivazou]

For some reason circleci didn't checkout the updated submodule..

@adinapoli didn't you fix that?

[adinapoli]

@nikivazou I've stumbled into something similar (i.e. the submodule fetching weirdness representing itself) while working on the GHC 8.10 patch.

I think my original fix was incomplete, because we have to crucially install ssh and git before checking out the code. Apologies for not noticing this sooner! I was going to eventually submit a fix as part of my ghc-8.10 branch, but as this might not land for a while, I will issue the one line fix to hopefully fix this for good. Sorry again!

[adinapoli]

Hopefully this PR should fix things for the better 🤞 #1610

[nikivazou]

@yiyunliu can you merge develop to this to check that it is ok?

Thanks!

[facundominguez]

@nikivazou, would you like getting this PR merged, or should we close it?