remove anchors and aaron from master template

General MR

Summary

Master template is used for provisioning new repos. By default we want to provision new repos with Mark Nelson being codeowners. They will be removed once. Remove anchors and aaron from master template.

Relevant logs/screenshots

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Linked Issue

Closes https://repo1.dso.mil/big-bang/repository-templates/master_template/-/issues/8

Upgrade Notices

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