Log missing file exception when failing to read metadata snapshot (#32920)

Adds the exception to the logged output, which contains info about the file that's missing.

Author: ginolzh

server/src/main/java/org/elasticsearch/index/store/Store.java

@@ -455,7 +455,7 @@ public static MetadataSnapshot readMetadataSnapshot(Path indexLocation, ShardId
         } catch (IndexNotFoundException ex) {
             // that's fine - happens all the time no need to log
         } catch (FileNotFoundException | NoSuchFileException ex) {
-            logger.info("Failed to open / find files while reading metadata snapshot");
+            logger.info("Failed to open / find files while reading metadata snapshot", ex);
         } catch (ShardLockObtainFailedException ex) {
             logger.info(() -> new ParameterizedMessage("{}: failed to obtain shard lock", shardId), ex);
         }