Add container logging known issue (#41119)

Add a known issue entry for 8.15.0 and 8.15.2 referencing
#41118.

CHANGELOG.asciidoc

@@ -7,6 +7,12 @@
 === Beats version 8.15.2
 https://github.com/elastic/beats/compare/v8.15.0\...v8.15.2[View commits]
 
+==== Known issues
+
+*Affecting all Beats*
+
+- Beats Docker images do not log to stderr by default. The workaround is to pass the CLI flag `-e` or to set `logging.to_stderr: true` in the configuration file. {issue}41118[41118]
+
 ==== Bugfixes
 
 *Affecting all Beats*
@@ -21,6 +27,12 @@ https://github.com/elastic/beats/compare/v8.15.0\...v8.15.2[View commits]
 === Beats version 8.15.1
 https://github.com/elastic/beats/compare/v8.15.0\...v8.15.1[View commits]
 
+==== Known issues
+
+*Affecting all Beats*
+
+- Beats Docker images do not log to stderr by default. The workaround is to pass the CLI flag `-e` or to set `logging.to_stderr: true` in the configuration file. {issue}41118[41118]
+
 ==== Bugfixes
 
 *Affecting all Beats*
@@ -69,6 +81,10 @@ https://github.com/elastic/beats/compare/v8.14.3\...v8.15.0[View commits]
 
 ==== Known issues
 
+*Affecting all Beats*
+
+- Beats Docker images do not log to stderr by default. The workaround is to pass the CLI flag `-e` or to set `logging.to_stderr: true` in the configuration file. {issue}41118[41118]
+
 *Filebeat*
 
 - The Azure EventHub input in Filebeat is not found when running on Windows. Please refrain from upgrading to 8.15. See {issue}40608[40608] for details.