[PATCH 2/2] t/Makefile: always test all lint targets when running tests

Only the two targets "test-lint-duplicates" and "test-lint-executable" are currently executed when running the test target. This was done on purpose when the TEST_LINT variable was added in 81127d74. But as this does not include the "test-lint-shell-syntax" target added the same day in commit c7ce70ac, it is easy to accidentally add non portable shell constructs without noticing that when running the test suite.

Fix that by always running all lint tests unless the TEST_LINT variable is
overridden. If we add less accurate or slow tests later we could still
fall back to exclude them like 81127d74 proposed. But for now it is better
to include all lint tests until proven otherwise.
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 t/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)