Remove the presentation template.

Moved to the presentation repo, to be in sync with changes there.

templates/presentation.yml

----
-presentation build:
-  stage: build
-  tags: [ns4.shore.co.il]
-  image:
-    name: registry.shore.co.il/presentation
-    entrypoint: [""]
-  before_script:
-    - |
-      [ -z "${PRESENTATION_ROOT:-}" ] || cd "$PRESENTATION_ROOT"
-  script:
-    - make --jobs=4
-  artifacts:
-    paths:
-      - '*.pdf'
-      - '**/*.pdf'