fix(cabal-install): cabal test runs the tests of the targets that have them

[zlonast]

fix: #11858

$ cabal test pkg-with-tests pkg-without-tests
No tests to run for the package pkg-without-tests-0.1.0.0
Running 1 test suites...
Test suite pkg-with-tests-test: PASS
1 of 1 test suites (1 of 1 test cases) passed.

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