flaky: TestWithEstimatorService in pkg/user

[rootulp]

Flaky test

Test: TestWithEstimatorService
Package: github.com/celestiaorg/celestia-app/v9/pkg/user
PR: #7073
CI run: https://github.com/celestiaorg/celestia-app/actions/runs/24420219491

Error

--- FAIL: TestWithEstimatorService (16.53s)
    network.go:79: tearing down testnode
    network.go:23: port binding error on attempt 1/5, retrying after 1s: listen tcp 127.0.0.1:43933: bind: address already in use
    network.go:79: tearing down testnode
    network.go:23: port binding error on attempt 2/5, retrying after 2s: failed to listen for privval gRPC: listen tcp 127.0.0.1:53658: bind: address already in use
    network.go:79: tearing down testnode
    network.go:23: port binding error on attempt 3/5, retrying after 3s: failed to listen for privval gRPC: listen tcp 127.0.0.1:53658: bind: address already in use
    network.go:79: tearing down testnode
    network.go:23: port binding error on attempt 4/5, retrying after 4s: failed to listen for privval gRPC: listen tcp 127.0.0.1:53658: bind: address already in use
    network.go:79: tearing down testnode
    network.go:23: port binding error on attempt 5/5, retrying after 5s: failed to listen for privval gRPC: listen tcp 127.0.0.1:53658: bind: address already in use

Notes

This test failure appears to be a flake — the failing test is not related to the changes in #7073 (which only modifies multiplexer/appd/run.go and multiplexer/appd/zipslip_test.go). The failure is caused by port binding conflicts (address already in use) during test node setup, which exhausts all 5 retry attempts.