Use SNAPSHOT in bwc tests to run tests with latest commits

[cwperks]

Description

The BWC Tests are not currently referring to a SNAPSHOT version when running testclusters which causes the distribution downloader to look for release or release-candidate versions of the minimum distribution as @saratvemulapalli describes here. This PR appends -SNAPSHOT to the versions supplied to testclusters to instruct testclusters to download a SNAPSHOT which will always have the most up-to-date changes included.

• Category (Enhancement, New feature, Bug fix, Test fix, Refactoring, Maintenance, Documentation)

Test fix

Issues Resolved

#3020

Check List

• New functionality includes testing
• New functionality has been documented
• Commits are signed per the DCO using --signoff

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[codecov]

Codecov Report

Merging #3024 (53c0fec) into main (37aacdc) will decrease coverage by 0.12%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##               main    #3024      +/-   ##
============================================
- Coverage     62.40%   62.29%   -0.12%     
+ Complexity     3377     3370       -7     
============================================
  Files           267      267              
  Lines         19772    19772              
  Branches       3355     3355              
============================================
- Hits          12339    12317      -22     
- Misses         5789     5812      +23     
+ Partials       1644     1643       -1     

see 7 files with indirect coverage changes