Update TableIndexReaderCache (#2223)

### What problem does this PR solve?
Fix `TableIndexReaderCache::Invalidate()`

Issue link:#2192

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

src/storage/invertedindex/column_index_reader.cpp

@@ -188,7 +188,6 @@ IndexReader TableIndexReaderCache::GetIndexReader(Txn *txn) {
             }
             String column_name = index_base->column_name();
             auto column_id = table_entry_ptr_->GetColumnIdByName(column_name);
-            assert(table_index_entry->GetFulltexSegmentUpdateTs() <= last_known_update_ts_);
             if (auto &target_ts = cache_column_ts[column_id]; target_ts < begin_ts) {
                 // need update result
                 target_ts = begin_ts;
@@ -226,7 +225,7 @@ IndexReader TableIndexReaderCache::GetIndexReader(Txn *txn) {
 void TableIndexReaderCache::Invalidate() {
     std::scoped_lock lock(mutex_);
     first_known_update_ts_ = 0;
-    last_known_update_ts_ = 0;
+    last_known_update_ts_ = std::max(last_known_update_ts_, cache_ts_);
     cache_ts_ = 0;
     cache_column_ts_.clear();
     cache_column_readers_.reset();