Fixes issue #11827 - Maven DI crashes if the file org.apache.maven.api.di.Inject contains empty lines

[jafarre-bi]

Adds a check to ignore blank lines when reading org.apache.maven.api.di.Inject.

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[cstamas]

Note: maybe just !isBlank()?

[jafarre-bi]

Not sure whether it had to be compatible with Java < 11

[cstamas]

Maven 4 (master and maven-4.0.x) is Java 17+

Also, you need to build locally (or apply spotless explicitly mvn spotless:apply) to reformat before pushing.

[jafarre-bi]

@cstamas ready

[jafarre-bi]

Thank you! Do I need to do anything else?