Add asciidoc build tag and remove pdf build stage from .gitlab-ci.yml

.gitlab-ci.yml

@@ -7,16 +7,18 @@ stages:
 
 html:
   stage: build
+  tags:
+     - asciidoc
   script: 
      - asciidoctor -r asciidoctor-diagram main.adoc -o P2020_OpenSCENARIO_2-0_Project_Proposal.html
   artifacts:
     paths:
      - P2020_OpenSCENARIO_2-0_Project_Proposal.html
 
-pdf:
-  stage: build
-  script: 
-     - asciidoctor-pdf -r asciidoctor-diagram -r asciidoctor-mathematical main.adoc -o P2020_OpenSCENARIO_2-0_Project_Proposal.pdf
-  artifacts:
-    paths:
-     - P2020_OpenSCENARIO_2-0_Project_Proposal.pdf
+# pdf:
+#   stage: build
+#   script: 
+#      - asciidoctor-pdf -r asciidoctor-diagram -r asciidoctor-mathematical main.adoc -o P2020_OpenSCENARIO_2-0_Project_Proposal.pdf
+#   artifacts:
+#     paths:
+#      - P2020_OpenSCENARIO_2-0_Project_Proposal.pdf