export type ScheduledTimerEventPayload (#626)

## Summary
Export type `ScheduledTimerEventPayload` as I need it in my TS project.


## Checklist
<!-- Tick these items off as you progress. -->
<!-- If an item isn't applicable, ideally please strikeout the item by
wrapping it in "~~"" and suffix it with "N/A My reason for skipping
this." -->
<!-- e.g. "- [ ] ~~Added tests~~ N/A Only touches docs" -->

- [ ] ~Added a [docs PR](https://github.com/inngest/website) that
references this PR~ N/A
- [ ] ~Added unit/integration tests~ N/A
- [ ] Added changesets if applicable

---------

Co-authored-by: Jack Williams <jpwilliamsphotography@gmail.com>

.changeset/tame-mirrors-clean.md

@@ -0,0 +1,5 @@
+---
+"inngest": patch
+---
+
+Export `ScheduledTimerEventPayload` for ESM

packages/inngest/src/index.ts

@@ -94,6 +94,7 @@ export type {
   LogLevel,
   OutgoingOp,
   RegisterOptions,
+  ScheduledTimerEventPayload,
   SendEventBaseOutput,
   StepOptions,
   StepOptionsOrId,