ci: intermittent issue in `p2p_segwit.py` #36700

https://github.com/bitcoin/bitcoin/actions/runs/40953304624/job/123726800969?pr=36673#step:11:27354:

[53](https://github.com/bitcoin/bitcoin/actions/runs/40953304624/job/123726800969?pr=36673#step:11:27354)
 test  2026-10-29T21:04:14.796377Z TestFramework (ERROR): Unexpected exception: 
                                   Traceback (most recent call last):
                                     File "/home/runner/work/_temp/test/functional/test_framework/test_framework.py", line 146, in main
                                       self.run_test()
                                     File "/home/runner/work/_temp/build_ ₿🧪_/test/functional/p2p_segwit.py", line 287, in run_test
                                       self.test_uncompressed_pubkey()
                                     File "/home/runner/work/_temp/build_ ₿🧪_/test/functional/p2p_segwit.py", line 113, in func_wrapper
                                       func(self, *args, **kwargs)
                                     File "/home/runner/work/_temp/build_ ₿🧪_/test/functional/p2p_segwit.py", line 1521, in test_uncompressed_pubkey
                                       test_witness_block(self.nodes[1], self.std_node, block, accepted=True)
                                     File "/home/runner/work/_temp/build_ ₿🧪_/test/functional/p2p_segwit.py", line 147, in test_witness_block
                                       assert_equal(node.getbestblockhash() == block.hash_hex, accepted)
                                     File "/home/runner/work/_temp/test/functional/test_framework/util.py", line 95, in assert_equal
                                       raise AssertionError("not(%s)" % " == ".join(str(arg) for arg in (thing1, thing2) + args))
                                   AssertionError: not(False == True)

Same on FreeBSD: https://github.com/hebasto/bitcoin-core-nightly/actions/runs/41011465948.

My clanker ran into a similar issue in the same sub-test here by running the functional tests under rr. It's related to this issue because the test assumes that giving a block to node0 means that node1 (edit: or vice versa) also immediately has it, which is non-deterministic.