it turns out that setting a timeout on HTTP client affect watch requests made by the delegated authentication component.
with a 10 second timeout watch requests are being re-established exactly after 10 seconds even though the default request timeout for them is ~5 minutes.
this is because if multiple timeouts were set, the stdlib picks the smaller timeout to be applied, leaving other useless.
for more details see a937729c2c/src/net/http/client.go (L364)
instead of setting a timeout on the HTTP client we should use context for cancellation.
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