Bump pypdf from 6.9.1 to 6.9.2 in /libs/langchain-mongodb in the uv group across 1 directory (#359)

Bumps the uv group with 1 update in the /libs/langchain-mongodb
directory: [pypdf](https://github.com/py-pdf/pypdf).

Updates `pypdf` from 6.9.1 to 6.9.2
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/py-pdf/pypdf/releases">pypdf's
releases</a>.</em></p>
<blockquote>
<h2>Version 6.9.2, 2026-03-23</h2>
<h2>What's new</h2>
<h3>Security (SEC)</h3>
<ul>
<li>Avoid infinite loop in read_from_stream for broken files (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3693">#3693</a>)
by <a
href="https://github.com/stefan6419846"><code>@​stefan6419846</code></a></li>
</ul>
<h3>Robustness (ROB)</h3>
<ul>
<li>Resolve UnboundLocalError for xobjs in _get_image (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3684">#3684</a>)
by <a
href="https://github.com/Yuki9814"><code>@​Yuki9814</code></a></li>
</ul>
<p><a href="https://github.com/py-pdf/pypdf/compare/6.9.1...6.9.2">Full
Changelog</a></p>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/py-pdf/pypdf/blob/main/CHANGELOG.md">pypdf's
changelog</a>.</em></p>
<blockquote>
<h2>Version 6.9.2, 2026-03-23</h2>
<h3>Security (SEC)</h3>
<ul>
<li>Avoid infinite loop in read_from_stream for broken files (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3693">#3693</a>)</li>
</ul>
<h3>Robustness (ROB)</h3>
<ul>
<li>Resolve UnboundLocalError for xobjs in _get_image (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3684">#3684</a>)</li>
</ul>
<p><a href="https://github.com/py-pdf/pypdf/compare/6.9.1...6.9.2">Full
Changelog</a></p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/py-pdf/pypdf/commit/da867f4961e4ac5ac9d751cba3131c5a1a8777f3"><code>da867f4</code></a>
REL: 6.9.2</li>
<li><a
href="https://github.com/py-pdf/pypdf/commit/02b1345f77fdbc006faccc301507df4fb1855413"><code>02b1345</code></a>
SEC: Avoid infinite loop in read_from_stream for broken files (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3693">#3693</a>)</li>
<li><a
href="https://github.com/py-pdf/pypdf/commit/3bef3393757d9ab711032cb07019ae3b8132ba42"><code>3bef339</code></a>
MAINT: Prefer bytearray over bytes in image_inline (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3692">#3692</a>)</li>
<li><a
href="https://github.com/py-pdf/pypdf/commit/04b0a38f56ade7ba8ab9ed2f2b83e86794a036d5"><code>04b0a38</code></a>
ROB: Resolve UnboundLocalError for xobjs in _get_image (<a
href="https://redirect.github.com/py-pdf/pypdf/issues/3684">#3684</a>)</li>
<li>See full diff in <a
href="https://github.com/py-pdf/pypdf/compare/6.9.1...6.9.2">compare
view</a></li>
</ul>
</details>
<br />


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