rcmgr: increase default connection memory limit to 32 MB

[marten-seemann]

Fixes #1706.

[vyzo]

16 is probably enough, but shouldnt be a problem.
You might also want to adjust the peer base limit to 16M at least.

[marten-seemann]

16 is probably enough, but shouldnt be a problem.

The maximum flow control window that quic-go uses is 15 MB, and we're reserving with 128 priority, so we'll need to set this to 30 MB at least. Will update the PR to use 32 MB.

[marten-seemann]

You might also want to adjust the peer base limit to 16M at least.

It's already at 64:

go-libp2p/p2p/host/resource-manager/limit_defaults.go

Lines 493 to 502 in 11279c6

	PeerBaseLimit: BaseLimit{
	ConnsInbound: 4,
	ConnsOutbound: 8,
	Conns: 8,
	StreamsInbound: 256,
	StreamsOutbound: 512,
	Streams: 512,
	Memory: 64 << 20,
	FD: 4,
	},