Automatic merge from submit-queue
[GarbageCollector] add absent owner cache
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**What this PR does / why we need it**:
Reducing the Request sent to the API server by the garbage collector to check if an owner exists.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
#26120
**Special notes for your reviewer**:
**Release note**:
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```release-note
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Currently when processing an item in the dirtyQueue, the garbage collector issues GET to check if any of its owners exist. If the owner is a replication controller with 1000 pods, the garbage collector sends a GET for the RC 1000 times. This PR caches the owner's UID if it does not exist according to the API server. This cuts 1/3 of the garbage collection time of the density test in the gce-500 and gce-scale, where the QPS is the bottleneck.
8f431e4af8