Show pipeline info and gitlab_templates version in composer log

Migrated issue

Reported by: jonathan1055

Related to !302 (merged)

Problem/Motivation

When providing support to admins and developers to help with failing pipelines it would be useful if certain information was always available in the log, so we can answer some questions without requesting a re-run etc.

Proposed resolution

• Display some key $CI_ variables in the composer log, regardless of the setting of _SHOW_ENVIRONMENT_VARIABLES
• Display the version of gitlab_templates that is being used