Fix winlog missing-channel integration expectations (#49017) (#49048)

Align TestWinlogIgnoreMissingChannel with the channel-not-found retry log message and stop asserting channel names no longer emitted on that path.

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Human-Reviewed: Yes
Tool: GitHub Copilot CLI, Model: GPT-5.3 Codex



(cherry picked from commit 35a560e)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 3 people

x-pack/filebeat/tests/integration/windows/inputs_windows_test.go

@@ -117,8 +117,7 @@ output.console:
 logging.level: info
 `,
 			expectedOutput: []string{
-				"ignoring open error",
-				"NonExistentChannel1",
+				"encountered channel not found error when opening Windows Event Log, retrying",
 			},
 		},
 		"explicit true ignores missing channels": {
@@ -133,7 +132,7 @@ output.console:
   enabled: true
 logging.level: info
 `,
-			expectedOutput: []string{"ignoring open error", "NonExistentChannel2"},
+			expectedOutput: []string{"encountered channel not found error when opening Windows Event Log, retrying"},
 		},
 		"explicit false fails on missing channels": {
 			configTemplate: `
@@ -147,7 +146,7 @@ output.console:
   enabled: true
 logging.level: debug
 `,
-			expectedOutput: []string{"NonExistentChannel3", "The specified channel could not be found", "encountered recoverable error"},
+			expectedOutput: []string{"The specified channel could not be found", "encountered channel not found error when opening Windows Event Log, retrying"},
 		},
 	}
 	for name, tc := range tcs {