chore: update repo semaphore config (#168)

Co-authored-by: service-bot-app[bot] <foo-bar+service-bot-app[bot]@users.noreply.github.com>

Author: service-bot-app[bot]

.semaphore/semaphore.yml

@@ -32,7 +32,7 @@ blocks:
     dependencies: []
     run:
       # don't run the tests on non-functional changes...
-      when: "change_in('/', {exclude: ['/.deployed-versions/', '.github/']})"
+      when: "change_in('/', {exclude: ['/.deployed-versions/', '.github/'], default_branch: 'master'})"
     task:
       jobs:
         - name: Test