release-26.2: ccl/changefeedccl: TestChangefeedProtectedTimestampUpdate failed

ccl/changefeedccl.TestChangefeedProtectedTimestampUpdate failed on release-26.2 @ b213c58ceafd70a2aa5d066a033d1e412ea9bd99:

=== RUN   TestChangefeedProtectedTimestampUpdate
    test_log_scope.go:172: test logs captured to: outputs.zip/logTestChangefeedProtectedTimestampUpdate4235393390
    test_log_scope.go:82: use -show-logs to present logs inline
    changefeed_test.go:13217: -- test log scope end --
test logs left over in: outputs.zip/logTestChangefeedProtectedTimestampUpdate4235393390
--- FAIL: TestChangefeedProtectedTimestampUpdate (6.29s)
=== RUN   TestChangefeedProtectedTimestampUpdate/kafka
    helpers_test.go:1606: making server as system tenant
    helpers_test.go:1682: making kafka feed factory
    testfeed_test.go:341: creating external connection
    testfeed_test.go:344: ran create external connection
    changefeed_test.go:13204: 
        	Error Trace:	pkg/ccl/changefeedccl/changefeed_test.go:13204
        	            				pkg/ccl/changefeedccl/helpers_test.go:1868
        	            				pkg/ccl/changefeedccl/helpers_test.go:1904
        	Error:      	"1" is not greater than or equal to "2"
        	Test:       	TestChangefeedProtectedTimestampUpdate/kafka
--- FAIL: TestChangefeedProtectedTimestampUpdate/kafka (6.28s)

Parameters:

• attempt=1
• run=1
• shard=16

Jira issue: CRDB-68565

Start with pkg/ccl/changefeedccl/changefeed_test.go around line 13204 and inspect the failure path through helpers_test.go lines 1868 and 1904. Re-run TestChangefeedProtectedTimestampUpdate, using the captured logs and the referenced test report to determine why the Kafka case observes 1 instead of at least 2. Done means the failure is understood and the test passes reliably.