fix: correct RELEASES.md format for Speakeasy publish (#333)

## Summary
- Adds missing trailing spaces to `- OpenAPI Doc` line in the 0.42.11
RELEASES.md entry
- Adds missing trailing newline at end of file
- The Speakeasy publish action failed with `error parsing last release
info` because the format didn't match the expected pattern

This unblocks the 0.42.11 PyPI publish.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Low risk: documentation-only formatting tweaks (trailing
spaces/newline) to satisfy Speakeasy release parsing; no runtime code
changes.
> 
> **Overview**
> Fixes the `2026-03-25` (`v0.42.11`) entry in `RELEASES.md` to match
Speakeasy’s expected release format by restoring the trailing spaces on
`- OpenAPI Doc` and ensuring the file ends with a proper final newline
(so the last `PyPI v0.42.11` line is parsed correctly).
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
39fd2ae. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: fxdgear

RELEASES.md

@@ -1195,9 +1195,9 @@ Based on:
 ## 2026-03-25 16:00:00
 ### Changes
 Based on:
-- OpenAPI Doc
+- OpenAPI Doc  
 - Speakeasy CLI 1.601.0 (2.680.0) https://github.com/speakeasy-api/speakeasy
 ### Generated
 - [python v0.42.11] .
 ### Releases
-- [PyPI v0.42.11] https://pypi.org/project/unstructured-client/0.42.11 - .
+- [PyPI v0.42.11] https://pypi.org/project/unstructured-client/0.42.11 - .