Automatic merge from submit-queue
Proxy min sync period
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**What this PR does / why we need it**:
Gives the proxy the option to set a lower bound on the sync period when there are a high number of endpoint changes. This prevents excessive iptables re-writes under a number of conditions.
fixes#33693
and alleviates the symptoms of #26637
**NOTE:**
There are other minor fixes that I'm working on but keeping the PRs separate.
**Release note**:
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`Added iptables-min-syn-period(2) to proxy to prevent excessive iptables writes`
dd53b749e4