Fail clearly when configureLocator has no project POM #275

[AzazelSensei]

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configureLocator() ran before the try/finally that restores the context classloader, and it called project.getFile().getParentFile() with no null check.

Moved the call into that block. If the project has no POM file, throw MojoExecutionException instead of a raw NPE.

• I hereby declare this contribution to be licenced under the Apache License Version 2.0, January 2004