fix(OpenSearchClient): boostScore totalVotes nullable checks

Using OpenSearch 2.9 an exception is  raised when we try to check if a property of long type is missing with doc['field'].value != null

openmetadata-service/src/main/java/org/openmetadata/service/search/opensearch/OpenSearchClient.java

@@ -654,7 +654,7 @@ private Response searchPipelineLineage(
  private static ScriptScoreFunctionBuilder boostScore() {
  return ScoreFunctionBuilders.scriptFunction(
  "double score = _score;"
- + "if (doc.containsKey('totalVotes') && doc['totalVotes'].value != null) { score = score + doc['totalVotes'].value; }"
+ + "if (doc.containsKey('totalVotes') && doc['totalVotes'].size() != 0) { score = score + doc['totalVotes'].value; }"
  + "if (doc.containsKey('usageSummary') && doc['usageSummary.weeklyStats.count'].value != null) { score = score + doc['usageSummary.weeklyStats.count'].value; }"
  + "if (doc.containsKey('tier.tagFQN') && !doc['tier.tagFQN'].empty) { if (doc['tier.tagFQN'].value == 'Tier.Tier2') { score = score + 10; }"
  + " else if (doc['tier.tagFQN'].value == 'Tier.Tier1') { score = score + 20; }}"