Prepackage Channel Export plugin v1.2.1 (#29638)

Co-authored-by: Mattermost Build <build@mattermost.com>

server/Makefile

@@ -161,6 +161,7 @@ PLUGIN_PACKAGES += mattermost-plugin-user-survey-v1.1.1
 PLUGIN_PACKAGES += mattermost-plugin-mscalendar-v1.3.4
 PLUGIN_PACKAGES += mattermost-plugin-msteams-meetings-v2.2.0
 PLUGIN_PACKAGES += mattermost-plugin-metrics-v0.5.3
+PLUGIN_PACKAGES += mattermost-plugin-channel-export-v1.2.1
 
 EE_PACKAGES=$(shell $(GO) list $(BUILD_ENTERPRISE_DIR)/...)