Update deploy test

Don't assume a branch name, but use the current branch. This is added so
the tests running in GitHub Actions don't break, as the git on there
still uses "master" as the default branch after "git init".

Author: bewuethr

test/deploy.bats

@@ -5,7 +5,7 @@ load test_helper
 @test "Run deploy" {
 	pbb init 'Testblog'
 	pbb build
-	git push --set-upstream origin main
+	git push --set-upstream origin "$(git branch --show-current)"
 	run pbb deploy
 
 	echo "$output"