Merge branch 'sk/t1100-modernize' into next

The test script 't/t1100-commit-tree-options.sh' has been modernized by converting test cases to the modern style (using single quotes and tab indentation) and moving the creation of the expected file inside the setup test so it runs under the protection of the test harness. * sk/t1100-modernize: t1100: move creation of expected output into setup test t1100: modernize test style