fix: changed Dockerfile for preview build and removed unused Dockerfiles (#3070)

Author: codechirag123

.github/workflows/build-preview-environment.yml

@@ -88,7 +88,7 @@ jobs:
       image_name: backoffice
       ref: ${{ needs.deploy-dev-pr-environment.outputs.ref }}
       tag: ${{ needs.deploy-dev-pr-environment.outputs.env_name }}
-      file: 'apps/backoffice-v2/Dockerfile.preview'
+      file: 'apps/backoffice-v2/Dockerfile'
 
   build-kyb:
     needs: [deploy-dev-pr-environment]
@@ -99,7 +99,7 @@ jobs:
       image_name: kyb-app
       ref: ${{ needs.deploy-dev-pr-environment.outputs.ref }}
       tag: ${{ needs.deploy-dev-pr-environment.outputs.env_name }}
-      file: 'apps/kyb-app/Dockerfile.preview'
+      file: 'apps/kyb-app/Dockerfile'
 
   build-dashboard:
     needs: [deploy-dev-pr-environment]
@@ -110,7 +110,7 @@ jobs:
       image_name: workflows-dashboard
       ref: ${{ needs.deploy-dev-pr-environment.outputs.ref }}
       tag: ${{ needs.deploy-dev-pr-environment.outputs.env_name }}
-      file: 'apps/workflows-dashboard/Dockerfile.preview'
+      file: 'apps/workflows-dashboard/Dockerfile'
 
   build-unified-api:
     runs-on: ubuntu-latest