Auth file: Ensure 0-termination #20

Job	Run time
coverity-test	0s
coverage-test	6m 7s
master-tss-build-test (gcc)	6m 3s
build-test (ubuntu-18.04, gcc)	5m 54s
master-tss-build-test (clang)	5m 18s
build-test (ubuntu-18.04, clang)	5m 18s
build-test (ubuntu-20.04, gcc)	6m 13s
build-test (ubuntu-20.04, clang)	4m 58s
build-test (fedora-30, gcc)	6m 6s
build-test (fedora-30, clang)	5m 32s
build-test (opensuse-leap, gcc)	6m 11s
build-test (opensuse-leap, clang)	5m 30s
build-test (fedora-32, gcc)	6m 3s
build-test (fedora-32, clang)	5m 13s
build-test (ubuntu-22.04, gcc)	11m 35s
build-test (ubuntu-22.04, clang)	11m 10s
	1h 37m 11s

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