Update .gitlab-ci.yml

.gitlab-ci.yml

-image: nextflow/nextflow
-push:
-  script:
-     - nextflow run ./main.nf --help
+# recipe for building singularity image and deploy it on the registery for bwa version 0.7.17
+image:
+   name: quay.io/singularity/singularity:v3.4.0
+   entrypoint: [""]
+
+stages:
+ - build
+ - deploy
+
+# Build Singularity container bwa_v0.7.17.sif
+singularity-image:
+   stage: build
+   script:
+       - singularity build metagWGS.sif env/Singularity_recipe_metagWGS_dependancies
+   artifacts:
+      paths:
+       - metagWGS.sif
+# Push the image template.sif on the registry
+deploy:
+   stage: deploy
+   script:
+       - singularity push --docker-username "${CI_REGISTRY_USER}" --docker-password "${CI_REGISTRY_PASSWORD}" metagWGS.sif oras://"$CI_REGISTRY_IMAGE"/"$CI_PROJECT_NAME":"$CI_COMMIT_TAG"