replace use of master with main

[jedwards4b]

Description of changes

Replace usage of master with main, both with reference to github branch and primary task in fortran code.

Specific notes

Contributors other than yourself, if any:

CMEPS Issues Fixed (include github issue #):

Are changes expected to change answers? (specify if bfb, different at roundoff, more substantial)

Any User Interface Changes (namelist or namelist defaults changes)?

Testing performed

Testing performed if application target is CESM:

• (recommended) CIME_DRIVER=nuopc scripts_regression_tests.py
  • machines:
  • details (e.g. failed tests):
• (recommended) CESM testlist_drv.xml
  • machines and compilers:
  • details (e.g. failed tests):
• (optional) CESM prealpha test
  • machines and compilers
  • details (e.g. failed tests):
• (other) please described in detail
  • machines and compilers
  • details (e.g. failed tests):

Testing performed if application target is UFS-coupled:

• (recommended) UFS-coupled testing
  • description:
  • details (e.g. failed tests):

Testing performed if application target is UFS-HAFS:

• (recommended) UFS-HAFS testing
  • description:
  • details (e.g. failed tests):

Hashes used for testing:

• CESM:
  • repository to check out: https://github.com/ESCOMP/CESM.git
  • branch/hash:
• UFS-coupled, then umbrella repostiory to check out and associated hash:
  • repository to check out:
  • branch/hash:
• UFS-HAFS, then umbrella repostiory to check out and associated hash:
  • repository to check out:
  • branch/hash:

[uturuncoglu]

@jedwards4b do we need to test it under UFS? It seems it is just replacing master with main and if it compiles under CESM, it will probably works under UFS too.