fix bloom filter posting format to get the fpp from the correct settings

src/main/java/org/elasticsearch/index/codec/postingsformat/BloomFilterPostingsFormatProvider.java

@@ -42,7 +42,7 @@ public BloomFilterPostingsFormatProvider(@IndexSettings Settings indexSettings,
         this.delegate = Helper.lookup(indexSettings, postingsFormatSettings.get("delegate"), postingFormatFactories);
         this.postingsFormat = new BloomFilterPostingsFormat(
                 delegate.get(),
-                BloomFilter.Factory.buildFromString(indexSettings.get("fpp"))
+                BloomFilter.Factory.buildFromString(postingsFormatSettings.get("fpp"))
         );
     }