Updated circleci to point to main branch

[projectLewis]

Updated circleci config to point to main branch instead of master branch

[projectLewis]

circleci is failing because terraform is looking for the branch with "master", I believe this should fix that.

Edit: It appears terraform may be having an access issue.

Warning: Permanently added the RSA host key for IP address '140.82.112.4' to the list of known hosts.
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

[projectLewis]

The conversation can be seen in slack, however the fix was deleting that in circleci and generating a new one. Which means this PR is unrelated to the issue. I'm going to leave this up because it still may be necessary to change master to main in this file. Can discuss further when everyone is back from holiday

[irvingpop]