GCC CI Build Fixes

[stefankiesz]

Issue #, if available:

What was changed? Updated the GCC path set in the Mac GCC CI build.

Why was it changed? "gcc" is mapped to CLANG on Mac, so the build was using CLANG rather than GCC compiler.

How was it changed? The full path to the GCC and G++ compiler was identified, and it replaced the "gcc" and "g++" in the respective environment variables.

What testing was done for the changes? The CI is to run to verify that the correct compiler is used and that the test is passing.

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 75.22%. Comparing base (f6bc9fc) to head (be796ac).

:exclamation: Current head be796ac differs from pull request most recent head 254f5a3. Consider uploading reports for the commit 254f5a3 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1861      +/-   ##
===========================================
- Coverage    75.44%   75.22%   -0.23%     
===========================================
  Files           49       48       -1     
  Lines        13930    12177    -1753     
===========================================
- Hits         10510     9160    -1350     
+ Misses        3420     3017     -403     

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[stefankiesz]

Note to self: add comments in code explaining changes before merging.