Address ion-test-driver failure by upgrading pip with setup-python action.

[nirosys]

Issue #, if available: #795

Description of changes:
It appears that the issue causing the ion-test-driver failure is related to an issue found in pip 22.0. This PR adds the setup-python action to force a pip upgrade (and ensure python version).

A run of the workflow can be seen here.

In addition to the setup-python change, I also had to roll-back the revision of ion-test-driver that was being used to before the 1.0 and 1.1 split was made. The workflow was pulling master, which has been using the directory split for a while, but it appears the iontests used by this repo is from before versioned directories were added.

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.67%. Comparing base (3c1b6b1) to head (ed96200).
Report is 54 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #875      +/-   ##
============================================
+ Coverage     67.23%   67.67%   +0.43%     
- Complexity     5484     5522      +38     
============================================
  Files           159      159              
  Lines         23025    22982      -43     
  Branches       4126     4108      -18     
============================================
+ Hits          15481    15553      +72     
+ Misses         6262     6155     -107     
+ Partials       1282     1274       -8     

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[tgregg]

Nice! Thanks for fixing this.

Note that we recently changed ion-tests to restore the old iontestdata directory: amazon-ion/ion-tests#93

Maybe we can just make a quick update to ion-test-driver to point the 1.0 branch at iontestdata so we can keep pointing at master here? (see amazon-ion/ion-test-driver@1815f9c)

[nirosys]

Yea, I'll put a PR together to update ion-test-driver to match the ion-tests change. I'll try to get that together before EoD, then I can set this PR back to use master.