exit beta mode (#484)

turn off beta mode so that the version packages pr creates a real
release

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---

## PR-Codex overview
This PR focuses on changing the mode in the `.changeset/pre.json` file
from `pre` to `exit`, indicating a shift in the release process.

### Detailed summary
- Changed the `mode` from `"pre"` to `"exit"` in the
`.changeset/pre.json` file.

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question}`

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.changeset/pre.json

@@ -1,5 +1,5 @@
 {
-  "mode": "pre",
+  "mode": "exit",
   "tag": "beta",
   "initialVersions": {
     "@celo/celocli": "5.2.3",