(WIP) Use latest nightly for MIRI runs

[alamb]

Which issue does this PR close?

Re #879

Rationale for this change

try to get a reliably passing MIRI run

The symptoms of the failing MIRI runs seem to be the same as would happen if the system OOM'd -- #879 (comment) so try running with latest nightly to see if that helps

I admit this is likely grasping at straws 🥤

[codecov-commenter]

Codecov Report

Merging #907 (0495bd0) into master (b79c600) will decrease coverage by 0.00%.
The diff coverage is n/a.

❗ Current head 0495bd0 differs from pull request most recent head e384ff1. Consider uploading reports for the commit e384ff1 to get more accurate results

@@            Coverage Diff             @@
##           master     #907      +/-   ##
==========================================
- Coverage   82.30%   82.30%   -0.01%     
==========================================
  Files         168      168              
  Lines       48026    48026              
==========================================
- Hits        39529    39528       -1     
- Misses       8497     8498       +1     

Impacted Files	Coverage Δ
parquet_derive/src/parquet_field.rs	66.21% <0.00%> (-0.23%)	⬇️
arrow/src/array/transform/mod.rs	85.20% <0.00%> (-0.14%)	⬇️
arrow/src/datatypes/datatype.rs	65.36% <0.00%> (+0.43%)	⬆️

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[alamb]

Passed once: https://github.com/apache/arrow-rs/runs/4084964161?check_suite_focus=true

Let's try it again

[alamb]

Passed again: https://github.com/apache/arrow-rs/runs/4085251355?check_suite_focus=true
am rerunning

[alamb]

aaand it fails: https://github.com/apache/arrow-rs/runs/4092391752?check_suite_focus=true 😢

[alamb]

I think the next best thing may be to disable the failing test in MIRI. Will try that

[alamb]

Closing in favor of #910