Stop using auto-parallelizable

[CRogers]

Before this PR

We use auto-parallelizable, an annotation processor we made that uses the worker api so forces Gradle to run tasks in parallel. At one point, using the worker api was necessary to indicate to Gradle that the task should be run in parallel. However, modern Gradle is way smarter and now you can just write a "normal task" and provided you don't do anything naughty (eg getProject() call inside a task action, or complex Gradle domain object input like Configuration) then it will run the task in parallel (these broadly correspond to the configuration cache rules). We now have errorprone checks in gradle-guide that should prevent most of these mistakes.

When rolling out javaCompiler, there are some failures (circle, PR) because auto-parallelizable packages an old version of goethe, which packages an old version of palantir-java-format, which does not work with a 25 compiler:

Caused by: java.lang.NoSuchMethodError: 'java.util.Queue com.sun.tools.javac.util.Log$DeferredDiagnosticHandler.getDiagnostics()'
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.JavaInput.buildToks(JavaInput.java:366)
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.JavaInput.buildToks(JavaInput.java:334)
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.JavaInput.<init>(JavaInput.java:272)
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.Formatter.getFormatReplacements(Formatter.java:297)
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.Formatter.formatSource(Formatter.java:284)
        at shadow.com.palantir.goethe.goethe.com.palantir.javaformat.java.Formatter.formatSource(Formatter.java:252)
        at com.palantir.goethe.DirectFormatterFacade.formatSource(DirectFormatterFacade.java:36)
        at com.palantir.goethe.Goethe.formatAsString(Goethe.java:54)
        at com.palantir.goethe.Goethe.formatAndEmit(Goethe.java:68)
        at com.palantir.gradle.autoparallelizable.Emitter.emit(Emitter.java:50)

After this PR

==COMMIT_MSG==
Stop using auto-parallelizable on tasks, instead use regular tasks.
==COMMIT_MSG==

Rely on our errorprones to ensure tasks are parallelisable, stop using this annotation processor.

Testing

Relying on the existing automated tests.

Possible downsides?

Technical breaking change, but no one seems to use these tasks directly thankfully, so should be fine.

Are Docs needed?

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Description

Stop using auto-parallelizable on tasks, instead use regular tasks.

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🐛 Fixes

• Stop using auto-parallelizable on tasks, instead use regular tasks. (#1954)