Flaky tests

[julienrbrt]

Tracking PR for flaky tests:

• TestStartup (https://github.com/evstack/ev-node/actions/runs/17489374477/job/49675433956)

--- FAIL: TestStartup (2.50s)
 single_sequencer_test.go:48: Node did not stop after context cancellation
FAIL

• TestFastSync (https://github.com/evstack/ev-node/actions/runs/17493712343/job/49689186276?pr=2626)

--- FAIL: TestFastDASync (32.57s)
 helpers_test.go:268: Error running node 1: error while starting header sync service: failed to fetch the genesis: header/p2p: failed to open a new stream: failed to dial: failed to dial 12D3KooWLABptnR7VVgyeeWv8CqVotCypuA7Kx5xJiCW3PaTbMta: all dials failed
 * [/ip4/127.0.0.1/tcp/40001] dial backoff
 full_node_integration_test.go:166: 
 	Error Trace:	/home/runner/work/ev-node/ev-node/node/full_node_integration_test.go:166
 	Error: 	Received unexpected error:
 	 	expected height > 2, got 0
 	Test: 	TestFastDASync
FAIL

• E2E tests (https://github.com/evstack/ev-node/actions/runs/17489374477/job/49675588314)
  This test may just be always failing, and now flaky. To be investigated.

 evm_full_node_e2e_test.go:445: 
 	Error Trace:	/home/runner/work/ev-node/ev-node/test/e2e/evm_full_node_e2e_test.go:445
 	Error: 	"7" is not greater than or equal to "65"
 	Test: 	TestEvmSequencerWithFullNodeE2E
 	Messages: 	Full node DA included height (7) should be >= block height before wait (65)
 sut_helper.go:198: Process stopped, pid: 27078

[julienrbrt]

those were fixed by @chatton within the refactor #2644