The monitoring indicators of consul_rpc_queries_blocking maybe not accurate

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#### Overview of the Issue

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#### Reproduction Steps

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1.when I watch a key, the consul_rpc_queries_blocking value will +1.

2.when I use Ctrl+c to cancel the watch, the consul_rpc_queries_blocking not -1.

So, Is there a delay in the statistics of this indicator ？Emmm ...How many seconds will this delay?