bug(streaming): TopNCache::estimated_heap_size wrong

[st1page]

Some user report that the memory metrics is wrong for streaming query with topN

It is because the TopNCacheState::extract_if and TopNCacheState::retain do not maintain the kv_size correctly.

risingwave/src/stream/src/executor/top_n/topn_cache_state.rs

Lines 111 to 124 in 8c77bb4

	pub fn extract_if<F>(&mut self, pred: F) -> ExtractIf<'_, CacheKey, CompactedRow, F, Global>
	where
	F: FnMut(&CacheKey, &mut CompactedRow) -> bool,
	{
	self.inner.extract_if(pred)
	}
	pub fn retain<F>(&mut self, f: F)
	where
	F: FnMut(&CacheKey, &mut CompactedRow) -> bool,
	{
	self.inner.retain(f)
	}
	}