/usr/share/installed-tests/evolution-data-server/test-book-client-custom-summary.test is in evolution-data-server-tests 3.28.1-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | [Test]
Type=session-exclusive
Exec=env TEST_INSTALLED_SERVICES=1 /usr/lib/evolution/evolution-data-server/installed-tests/test-book-client-custom-summary
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