Bumping prepackaged gitlab plugin version to 1.12.3 (#37208)

Automatic Merge

server/Makefile

@@ -144,7 +144,7 @@ TEMPLATES_DIR=templates
 PLUGIN_PACKAGES ?= $(PLUGIN_PACKAGES:)
 PLUGIN_PACKAGES += mattermost-plugin-calls-v1.11.4
 PLUGIN_PACKAGES += mattermost-plugin-github-v2.7.0
-PLUGIN_PACKAGES += mattermost-plugin-gitlab-v1.12.2
+PLUGIN_PACKAGES += mattermost-plugin-gitlab-v1.12.3
 PLUGIN_PACKAGES += mattermost-plugin-jira-v4.7.0
 # We need to prepackage both versions of playbooks and install the correct one based on the server license. See MM-60025.
 PLUGIN_PACKAGES += mattermost-plugin-playbooks-v1.41.1