fabtests/ucx: disable fi_rdm_tagged_peek ucx test

fi_rdm_tagged_peek is failing on cleanup path.
ft_free_res() -> ft_close_fids() -> fi_close() -> ucx_ep_close()
-> ucp_worker_destroy() -> ucp_worker_discard_uct_ep_progress()
-> ucp_ep_destroy_base() -> __funlockfile()

The reported error is:
"Segmentation fault: address not mapped to object at address 0x8"

This is a race condition and does not occur every time.
To reproduce run:
server: fi_rdm_tagged_peek -p ucx -E
client: fi_rdm_tagged_peek -p ucx -E server_address

Issue 10126 is tracking this bug. Re-enable this test when it is resolved.

Signed-off-by: Zach Dworkin <[email protected]>

fabtests/test_configs/ucx/ucx.exclude

@@ -43,3 +43,6 @@ writedata
 rdm_atomic
 # FI_INJECT_COMPLETE not supported
 -A inj_complete
+
+# Fails as a race condition because of segfault
+rdm_tagged_peek