ci(unit tests): discovery tests, flakey test "did not discover peer on time"

[ramin]

• TestDiscovery

flakey tests intermittently with race detector

2024/01/18 13:37:23 failed to sufficiently increase receive buffer size (was: 208 kiB, wanted: 2048 kiB, got: 416 kiB). See https://github.com/quic-go/quic-go/wiki/UDP-Buffer-Sizes for details.
--- FAIL: TestDiscovery (20.00s)
    discovery_test.go:67: did not discover peer in time

https://github.com/celestiaorg/celestia-node/actions/runs/7570583591/job/20616824070