Better testing for journal corruption

go/store/nbs/journal_chunk_source.go

@@ -243,7 +243,7 @@ func (s journalChunkSource) iterateAllChunks(ctx context.Context, cb func(chunks
 			return true
 		}
 
-		// We only have 16bytes of the hash. The value returned here will have 4 0x00 bytes at the end.
+		// We only have 16 bytes of the hash. The value returned here will have 4 0x00 bytes at the end.
 		var h hash.Hash
 		copy(h[:], a16[:])
 

integration-tests/bats/fsck.bats

@@ -78,5 +78,5 @@ make_updates() {
 
     run dolt fsck
     [ "$status" -eq 1 ]
-    [[ "$output" =~ "Chunk: 7i48kt4h41hcjniri7scv5m8a69cdn13 load failed with error: checksum error" ]] || false
+    [[ "$output" =~ "Chunk: 7i48kt4h41hcjniri7scv5m8a69cdn13 content hash mismatch: hitg0bb0hsakip96qvu2hts0hkrrla9o" ]] || false
 }