CI: Re-schedule weekly builds

Builds are now created on Monday and Thursday at 05:30.

.circleci/config.yml

@@ -119,7 +119,7 @@ workflows:
   weekly:
     triggers:
       - schedule:
-          cron: "48 15 * * 4"
+          cron: "30 5 * * 1,4"
           filters:
             branches:
               only:

docker/rebuild.sh

@@ -13,7 +13,7 @@
 set -euo pipefail
 
 SUPPORTED_BRANCH_NAMES=("master")
-SUPPORTED_TAG_PATTERNS=("^v2.1.\([6789]\|1[0-9]\)$")
+SUPPORTED_TAG_PATTERNS=("^v2.1.\([89]\|1[0-9]\)$")
 IMAGE_NAME=threema/threema-web
 
 if [ "${1:-}" = "--dry-run" ]; then