Remove static image generation steps/workflow

We've transitioned to using an iFrame for the SARS-CoV-2 forecasts
page in nextstrain.org¹ so we no longer need to generate the static
images as part of the automated workflow.

I still left the static-images.js script since it is a nice way to
generate static images of the viz.

¹ nextstrain/nextstrain.org#691

Snakefile

@@ -82,16 +82,6 @@ def _get_all_input(w):
                 date=run_date
             ))
 
-            if config.get("trigger_static_model_viz", False):
-                # Currently we only support gisaid/nextstrain_clades/global model results
-                all_input.extend(expand(
-                    "results/{data_provenance}/{variant_classification}/{geo_resolution}/{date}_trigger_static_model_viz.done",
-                    data_provenance=[data_provenance for data_provenance in data_provenances if data_provenance == "gisaid"],
-                    variant_classification=[variant_classification for variant_classification in variant_classifications if variant_classification == "nextstrain_clades"],
-                    geo_resolution=[geo_resolution for geo_resolution in geo_resolutions if geo_resolution == "global"],
-                    date=run_date
-                ))
-
     return all_input
 
 
@@ -107,4 +97,3 @@ if config.get("send_slack_notifications"):
 
 if config.get("upload"):
     include: "workflow/snakemake_rules/upload.smk"
-    include: "workflow/snakemake_rules/trigger.smk"

config/optional.yaml

@@ -10,6 +10,3 @@ upload:
 
 # Send Slack notifications
 send_slack_notifications: True
-
-# Trigger static model viz workflow
-trigger_static_model_viz: True