[Fix #201]: Add OSGi dependency on SpotBugs

[kgibm]

No description provided.

[kgibm]

@jasonk000 @krumts I'm not an expert in OSGi, so not sure the best way to fix this.

[kgibm]

Adding the com.github.spotbugs.plugin.eclipse dependency in the two MANIFEST.MF files causes a Tycho build error:

[ERROR] Cannot resolve project dependencies:
[ERROR]   Software being installed: org.eclipse.mat.api 1.17.0.qualifier
[ERROR]   Missing requirement: org.eclipse.mat.api 1.17.0.qualifier requires 'java.package; edu.umd.cs.findbugs.annotations 0.0.0' but it could not be found

This is resolved by adding the following to parent/pom.xml:

<repositories>
    <repository>
        <id>spotbugs-eclipse-site</id>
        <layout>p2</layout>
        <url>https://spotbugs.github.io/eclipse/</url>
    </repository>
</repositories>

But that results in Eclipse Dash license vetting failures which I don't know much about:

[INFO] License information could not be automatically verified for the following content:
[INFO] 
[INFO] p2/orbit/p2.eclipse.feature/com.github.spotbugs.plugin.eclipse/4.10.4.r202608200320-1a58a48
[INFO] p2/orbit/p2.eclipse.plugin/com.github.spotbugs.plugin.eclipse/4.10.4.r202608200320-1a58a48
[INFO] 
[INFO] This content is either not correctly mapped by the system, or requires review.
[INFO] Summary file was written to: /Users/kevin/git/mat/parent/target/dash/summary
[ERROR] Dependency license check failed. Some dependencies need to be vetted.

[kgibm]

Close in favor of #205