ci: Adds manual trigger for release-please (#557)

## What ❔
Adds manual trigger for release-please.
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## Why ❔

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## Checklist

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.github/workflows/release-please.yml

@@ -2,6 +2,7 @@ on:
   push:
     branches:
       - main
+  workflow_dispatch:
 
 permissions:
   contents: write