Remove duplicate SCTE-35 format and add sample to TsExtractorTest

It's not clear why we're currently outputting the format in both init()
and consume() - it seems likely that this was accidentally introduced
in <unknown commit>
when we started outputting the format in consume() but didn't remove it
from init().

library/core/src/main/java/com/google/android/exoplayer2/extractor/ts/SpliceInfoSectionReader.java

@@ -38,8 +38,6 @@ public final class SpliceInfoSectionReader implements SectionPayloadReader {
     this.timestampAdjuster = timestampAdjuster;
     idGenerator.generateNewId();
     output = extractorOutput.track(idGenerator.getTrackId(), C.TRACK_TYPE_METADATA);
-    output.format(Format.createSampleFormat(idGenerator.getFormatId(), MimeTypes.APPLICATION_SCTE35,
-        null, Format.NO_VALUE, null));
   }
 
   @Override