MB-47604: Pass CompactionConfig by value and use std::move

So that in a future patch which tweaks other parts of this ctor
clang-tidy doesn't complain about this.

Change-Id: Ide518acfe577ebe0ad4e3bf05b87a9d332f17bd7
Reviewed-on: http://review.couchbase.org/c/kv_engine/+/163193
Tested-by: Build Bot <[email protected]>
Reviewed-by: Richard de Mellow <[email protected]>

Author: BenHuddleston

engines/ep/src/kvstore/kvstore.h

@@ -143,11 +143,11 @@ enum class PurgedItemType {
 
 struct CompactionContext {
     CompactionContext(Vbid vbid,
-                      const CompactionConfig& config,
+                      CompactionConfig config,
                       uint64_t purgeSeq,
                       std::optional<time_t> timeToExpireFrom = {})
         : vbid(vbid),
-          compactConfig(config),
+          compactConfig(std::move(config)),
           rollbackPurgeSeqno(purgeSeq),
           timeToExpireFrom(timeToExpireFrom) {
     }