.gitlab-ci.yml: remove --rerun-triggers

It appears that presence of mtime in the list is simply ignored by
Snakemake. Probably, it's not possible to run with ignoring mtimes.

.gitlab-ci.yml

@@ -5,7 +5,7 @@ variables:
   DETECTOR_CONFIG: epic_craterlake
   GITHUB_SHA: ''
   GITHUB_REPOSITORY: ''
-  SNAKEMAKE_FLAGS: '--cache --rerun-triggers code input params software-env'
+  SNAKEMAKE_FLAGS: '--cache'
 
 workflow:
   name: '$PIPELINE_NAME'