ParDo requires its input to use KvCoder in order to use state and timers.
java.lang.IllegalArgumentException: ParDo requires its input to use KvCoder in order to use state and timers.
    at org.apache.beam.sdk.repackaged.com.google.common.base.Preconditions.checkArgument(Preconditions.java:383)
    at org.apache.beam.sdk.transforms.ParDo.validateStateApplicableForInput(ParDo.java:463)
    at org.apache.beam.sdk.transforms.ParDo.access$300(ParDo.java:423)
    at org.apache.beam.sdk.transforms.ParDo$MultiOutput.expand(ParDo.java:768)
    at org.apache.beam.sdk.transforms.ParDo$MultiOutput.expand(ParDo.java:703)
    at org.apache.beam.sdk.Pipeline.applyInternal(Pipeline.java:525)
    at org.apache.beam.sdk.Pipeline.applyTransform(Pipeline.java:460)
    at org.apache.beam.sdk.values.PCollection.apply(PCollection.java:284)
    at org.apache.beam.sdk.transforms.ParDo$SingleOutput.expand(ParDo.java:644)
    at org.apache.beam.sdk.transforms.ParDo$SingleOutput.expand(ParDo.java:582)
    at org.apache.beam.sdk.Pipeline.applyInternal(Pipeline.java:525)
    at org.apache.beam.sdk.Pipeline.applyTransform(Pipeline.java:479)
    at org.apache.beam.sdk.values.PCollection.apply(PCollection.java:297)
    at com.spotify.scio.values.PCollectionWrapper.applyInternal(PCollectionWrapper.scala:44)
    at com.spotify.scio.values.PCollectionWrapper.applyInternal$(PCollectionWrapper.scala:42)
    at com.spotify.scio.values.SCollectionImpl.applyInternal(SCollection.scala:1268)
    at com.spotify.scio.values.PCollectionWrapper.pApply(PCollectionWrapper.scala:54)
    at com.spotify.scio.values.PCollectionWrapper.pApply$(PCollectionWrapper.scala:46)
    at com.spotify.scio.values.SCollectionImpl.pApply(SCollection.scala:1268)
    at com.spotify.scio.values.SCollection.applyTransform(SCollection.scala:134)
    at com.spotify.scio.values.SCollection.applyTransform$(SCollection.scala:132)
    at com.spotify.scio.values.SCollectionImpl.applyTransform(SCollection.scala:1268)