CI: fix docker tag format on main branch and missing dependency on ci-frontend-metrics.sh (#74753)

* On main, set the docker tag format to be the same as it is in PRs

* Install bash when trying to push frontend metrics

scripts/drone/pipelines/build.star

@@ -98,7 +98,13 @@ def build_e2e(trigger, ver_mode):
             [
                 store_storybook_step(trigger = trigger_oss, ver_mode = ver_mode),
                 frontend_metrics_step(trigger = trigger_oss),
-                rgm_build_docker_step("packages.txt", images["ubuntu"], images["alpine"]),
+                rgm_build_docker_step(
+                    "packages.txt",
+                    images["ubuntu"],
+                    images["alpine"],
+                    tag_format = "{{ .version_base }}-{{ .buildID }}-{{ .arch }}",
+                    ubuntu_tag_format = "{{ .version_base }}-{{ .buildID }}-ubuntu-{{ .arch }}",
+                ),
                 publish_images_step(
                     docker_repo = "grafana",
                     trigger = trigger_oss,

scripts/drone/steps/lib.star

@@ -633,6 +633,7 @@ def frontend_metrics_step(trigger = None):
         },
         "failure": "ignore",
         "commands": [
+            "apk add --update bash",
             "./scripts/ci-frontend-metrics.sh | ./bin/build publish-metrics $${GRAFANA_MISC_STATS_API_KEY}",
         ],
     }