add cron to docker build CIs

.github/workflows/foxy-docker-build.yml

@@ -1,6 +1,10 @@
 name: Foxy Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   foxy_docker_build:

.github/workflows/galactic-docker-build.yml

@@ -1,6 +1,10 @@
 name: Galactic Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   galactic_docker_build:

.github/workflows/humble-docker-build.yml

@@ -1,6 +1,10 @@
 name: Humble Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   humble_docker_build:

.github/workflows/iron-docker-build.yml

@@ -1,6 +1,10 @@
 name: Iron Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   iron_docker_build:

.github/workflows/jazzy-docker-build.yml

@@ -1,6 +1,10 @@
 name: Jazzy Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   jazzy_docker_build:

.github/workflows/rolling-docker-build.yml

@@ -1,6 +1,10 @@
 name: Rolling Docker Build
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: "0 5 * * 1"
 
 jobs:
   rolling_docker_build: