Refactor deployment workflows for different branches

- Update the branch filter in `.github/workflows/deploy-to-cb.yml` to only trigger on the `dev` branch.
- Update the branch filter in `.github/workflows/deploy-to-heroku.yml` to only trigger on the `master` branch.
- Modify the matrix of app names in both workflows.

These changes ensure that deployments are triggered correctly based on the respective branches.

.github/workflows/deploy-to-cb.yml

@@ -1,15 +1,17 @@
 name: Deploy to Heroku
 
 on:
-  push: ["main"]
+  push:
+    branches:
+      - dev
   workflow_dispatch:
 
 jobs:
   deploy:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        app_name: ['unistudents-prod-1', 'unistudents-prod-4', 'unistudents-prod-5', 'unistudents-prod-6']
+        app_name: [ 'unistudents-uat' ]
     steps:
       - name: Checkout
         uses: actions/checkout@v2

.github/workflows/deploy-to-heroku.yml

@@ -1,15 +1,17 @@
 name: Deploy to Heroku
 
 on:
-  push: ["dev"]
+  push:
+    branches:
+      - master
   workflow_dispatch:
 
 jobs:
   deploy:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        app_name: ['unistudents-uat']
+        app_name: ['unistudents-prod-1', 'unistudents-prod-4', 'unistudents-prod-5', 'unistudents-prod-6']
     steps:
       - name: Checkout
         uses: actions/checkout@v2