Bump submodules/openssl from 21e0ed1 to efd81f8 (#5977)

Bumps [submodules/openssl](https://github.com/openssl/openssl) from
`21e0ed1` to `efd81f8`.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/openssl/openssl/commit/efd81f844e07908df0933a660487fa31550c0a98"><code>efd81f8</code></a>
Check wrlmethod existence before sending alert</li>
<li><a
href="https://github.com/openssl/openssl/commit/40365a6fbf3537335a9da0e53a765d258dd8a918"><code>40365a6</code></a>
Update description of OSSL_HTTP_adapt_proxy()</li>
<li><a
href="https://github.com/openssl/openssl/commit/b93d381caf1a6cf2351a5499063eb0fdcd1ef285"><code>b93d381</code></a>
Add test for empty proxy server adaptation</li>
<li><a
href="https://github.com/openssl/openssl/commit/c44f3a1d7666d3064a29715cb3d9f4ba24b59507"><code>c44f3a1</code></a>
Add check for empty server host in http_lib.c</li>
<li><a
href="https://github.com/openssl/openssl/commit/61c7c545f8fdf02120d2079fb8b05df03ecfc111"><code>61c7c54</code></a>
Make SSL_get_stream_write_state() safe for concluded streams</li>
<li><a
href="https://github.com/openssl/openssl/commit/089907c96290da8bbbf26e1071ad8059ae77fdcc"><code>089907c</code></a>
Fix record layer leak when swapping chained transport BIO</li>
<li><a
href="https://github.com/openssl/openssl/commit/7fa0d9a20e6b7043e2c492d550b28d771b84e70f"><code>7fa0d9a</code></a>
ssl/quic/quic_port.c: fix leak in port_make_channel()</li>
<li><a
href="https://github.com/openssl/openssl/commit/b3e6076eb9ace422d3f230e716c14580ed7cf193"><code>b3e6076</code></a>
Increase the query cache insert grow retry</li>
<li><a
href="https://github.com/openssl/openssl/commit/06212590444ff248dd06a39f890dd548d4632a7d"><code>0621259</code></a>
crypto/hashtable/hashtable.c: fix hashtable grow cleanup for aligned
allocation</li>
<li><a
href="https://github.com/openssl/openssl/commit/08b02ed9c1e6d401ef04ec7a07380533bb3d1a12"><code>08b02ed</code></a>
Handle NULL-buffer size probe in ossl_param_build_set_bn_pad()</li>
<li>Additional commits viewable in <a
href="https://github.com/openssl/openssl/compare/21e0ed12757d42eab23b48be1556ba3000f6d795...efd81f844e07908df0933a660487fa31550c0a98">compare
view</a></li>
</ul>
</details>
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