feat(ci): add manual trigger to build and publish workflow

Added `workflow_dispatch` event to allow manual triggering of the build and publish workflow.

.github/workflows/build-and-publish.yaml

@@ -1,15 +1,18 @@
 name: Build and push
 
 on:
+  workflow_dispatch:
+
   schedule:
     - cron: "49 5 * * *"
+
   push:
     branches: ["main"]
     # Publish semver tags as releases.
     tags: ["v*.*.*"]
+
   pull_request:
     branches: ["main"]
-
 env:
   # github.repository as <account>/<repo>
   IMAGE_NAME: cyberchef