Remove exclusion of META-INF/versions/9/OSGI-INF/MANIFEST.MF.

[copybara-service]

Remove exclusion of META-INF/versions/9/OSGI-INF/MANIFEST.MF.

JSpecify 1.0.1 removed that file from the JSpecify jar.

(You can see the history of why the exclusion was added in 2517f1b.)

I do notice some other preexisting shading-related diagnostics, though they are only warnings:

[INFO] --- shade:3.6.2:shade (default) @ error_prone_refaster ---
[WARNING] error_prone_core-1.0-HEAD-SNAPSHOT-with-dependencies.jar, error_prone_refaster-1.0-HEAD-SNAPSHOT.jar define 2 overlapping resources:
[WARNING]   - META-INF/MANIFEST.MF
[WARNING]   - META-INF/services/com.sun.source.util.Plugin
[WARNING] maven-shade-plugin has detected that some files are
[WARNING] present in two or more JARs. When this happens, only one
[WARNING] single version of the file is copied to the uber jar.
[WARNING] Usually this is not harmful and you can skip these warnings,
[WARNING] otherwise try to manually exclude artifacts based on
[WARNING] mvn dependency:tree -Ddetail=true and the above output.
[WARNING] See https://maven.apache.org/plugins/maven-shade-plugin/

I also notice this:

[INFO] --- bnd:7.3.0:bnd-process (generate-OSGi-manifest) @ error_prone_refaster ---
[WARNING] Cannot consider developer in line '57' of file '/usr/local/google/home/cpovirk/clients/error-prone-white/error-prone/pom.xml' for bundle header 'Bundle-Developers' as it does not contain the mandatory id.

Again, that's unrelated.