Handle pomTarget without a parent directory (#169)

[elharo]

Fixes #169

Problem

CreatePom.execute() threw a NullPointerException when pomTarget was a bare relative filename such as pom.xml. For such a value new File("pom.xml").getParentFile() returns null, so the parent-dir check failed.

Fix

Resolve a bare pomTarget against the Ant project base dir before creating the parent directory. The POM is now written to ${basedir}/pom.xml, matching the expected behavior of writing to the current working directory / project base dir. Targets with a directory component (e.g. out/pom.xml) behave as before.

Test

New CreatePomNoParentDirTest unit test reproduces the crash: it runs the task with pomTarget="pom.xml" and a project base dir, and asserts the POM is written to ${basedir}/pom.xml. Before the fix it fails with the NPE above; after the fix it passes.

All 55 tests pass (mvn verify).

[elharo]

The CI failure was in the Ant smoke-test target (build.xml:98), which uses a JUnit 3-style <junit> batch run: it reported No tests found in CreatePomNoParentDirTest and failed the build.

The test class was missing the public static junit.framework.Test suite() method that every other test class provides (see CreatePomTest, CreatePomRainyDayTest, etc.) so the Ant runner could not discover its tests.

Added the suite() method backed by JUnit4TestAdapter (plus the required junit.framework.JUnit4TestAdapter import). Verified with mvn -Prun-its verify: the smoke-test now runs CreatePomNoParentDirTest (1 test, 0 failures) and the full build passes.