Bump version to 3.7.0b1

[dreambeyondorange]

Checklist

• Make sure you are pointing to the right branch and add a label in the PR title (i.e. 2.x vs 3.x)
• Check all commits' messages are clear, describing what and why vs how.
• Make sure to have added unit tests or integration tests to cover the new/modified code.
• Check if documentation is impacted by this change.

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[codecov]

Codecov Report

Merging #2384 (251475c) into release-3.7 (485e2a9) will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           release-3.7    #2384   +/-   ##
============================================
  Coverage        70.34%   70.34%           
============================================
  Files               13       13           
  Lines             1851     1851           
============================================
  Hits              1302     1302           
  Misses             549      549           

Flag	Coverage Δ
unittests	70.34% <ø> (ø)

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[gmarciani]

I expected many more changes than just these two files. See example of version bump: https://github.com/aws/aws-parallelcluster-cookbook/pull/2383/files

[dreambeyondorange]

I expected many more changes than just these two files. See example of version bump: https://github.com/aws/aws-parallelcluster-cookbook/pull/2383/files

I did as well. But most of the bump script uses the short version and this aligns with previous beta bumps https://github.com/aws/aws-parallelcluster-cookbook/pull/2027/files. I don't see the system_tests/ dir any longer so I don't think that change is relevant