Fix wrong compression type and options in universal compaction picker (#10515)

Summary:
In UniversalCompactionBuilder::PickCompactionToReduceSortedRuns, we passed start_level to get compression type and options. I think that is wrong and we should use output_level instead.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10515

Reviewed By: hx235

Differential Revision: D38611335

Pulled By: ajkr

fbshipit-source-id: bb860caed4b6c6bbde8f75fc50cf875a9f04723d

db/compaction/compaction_picker_universal.cc

@@ -755,9 +755,9 @@ Compaction* UniversalCompactionBuilder::PickCompactionToReduceSortedRuns(
                                             kCompactionStyleUniversal),
                         GetMaxOverlappingBytes(), path_id,
                         GetCompressionType(vstorage_, mutable_cf_options_,
-                                           start_level, 1, enable_compression),
+                                           output_level, 1, enable_compression),
                         GetCompressionOptions(mutable_cf_options_, vstorage_,
-                                              start_level, enable_compression),
+                                              output_level, enable_compression),
                         Temperature::kUnknown,
                         /* max_subcompactions */ 0, grandparents,
                         /* is manual */ false, /* trim_ts */ "", score_,