tests: drop files from exclusion list in test-check-module-imports.t Now, these files has no style issue at checking with import-checker.py. BTW, tests/test-imports-checker.t is still excluded, because almost all code fragments in it has intentional importing style violation. Using NO_CHECK_EOF instead of EOF as heredoc limit mark can make import-checker.py ignore such fragments. But keeping these fragments checkable seems still useful: for example, test-imports-checker.t can be used to test whether import-checker.py can detect erroneous code fragment in test script as expected.