build(deps): Bump serde from 1.0.204 to 1.0.209 in /rust (#6440)

Bumps [serde](https://github.com/serde-rs/serde) from 1.0.204 to
1.0.209.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/serde-rs/serde/releases">serde's
releases</a>.</em></p>
<blockquote>
<h2>v1.0.209</h2>
<ul>
<li>Fix deserialization of empty structs and empty tuples inside of
untagged enums (<a
href="https://redirect.github.com/serde-rs/serde/issues/2805">#2805</a>,
thanks <a
href="https://github.com/Mingun"><code>@​Mingun</code></a>)</li>
</ul>
<h2>v1.0.208</h2>
<ul>
<li>Support serializing and deserializing unit structs in a
<code>flatten</code> field (<a
href="https://redirect.github.com/serde-rs/serde/issues/2802">#2802</a>,
thanks <a
href="https://github.com/jonhoo"><code>@​jonhoo</code></a>)</li>
</ul>
<h2>v1.0.207</h2>
<ul>
<li>Improve interactions between <code>flatten</code> attribute and
<code>skip_serializing</code>/<code>skip_deserializing</code> (<a
href="https://redirect.github.com/serde-rs/serde/issues/2795">#2795</a>,
thanks <a
href="https://github.com/Mingun"><code>@​Mingun</code></a>)</li>
</ul>
<h2>v1.0.206</h2>
<ul>
<li>Improve support for <code>flatten</code> attribute inside of enums
(<a
href="https://redirect.github.com/serde-rs/serde/issues/2567">#2567</a>,
thanks <a
href="https://github.com/Mingun"><code>@​Mingun</code></a>)</li>
</ul>
<h2>v1.0.205</h2>
<ul>
<li>Use serialize_entry instead of serialize_key + serialize_value when
serialize flattened newtype enum variants (<a
href="https://redirect.github.com/serde-rs/serde/issues/2785">#2785</a>,
thanks <a
href="https://github.com/Mingun"><code>@​Mingun</code></a>)</li>
<li>Avoid triggering a collection_is_never_read lint in the
deserialization of enums containing flattened fields (<a
href="https://redirect.github.com/serde-rs/serde/issues/2791">#2791</a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="30752ac4ff"><code>30752ac</code></a>
Release 1.0.209</li>
<li><a
href="b84e6ca4f5"><code>b84e6ca</code></a>
Improve wording of PR 2805 comments</li>
<li><a
href="87a2fb0f1a"><code>87a2fb0</code></a>
Wrap comments from PR 2805 to 80 columns</li>
<li><a
href="9eaf7b9824"><code>9eaf7b9</code></a>
Merge pull request <a
href="https://redirect.github.com/serde-rs/serde/issues/2805">#2805</a>
from Mingun/untagged-tests</li>
<li><a
href="7bde100237"><code>7bde100</code></a>
Replace MapRefDeserializer with value::MapDeserializer</li>
<li><a
href="da7fc795ee"><code>da7fc79</code></a>
Fix deserialization of empty struct variant in untagged enums</li>
<li><a
href="4c5fec1363"><code>4c5fec1</code></a>
Test special cases that reaches SeqRefDeserializer::deserialize_any
len==0 co...</li>
<li><a
href="6588b0ad37"><code>6588b0a</code></a>
Cover Content::Seq case in VariantRefDeserializer::struct_variant</li>
<li><a
href="0093f74cfe"><code>0093f74</code></a>
Split test newtype_enum into four tests for each variant</li>
<li><a
href="171c6da57a"><code>171c6da</code></a>
Complete coverage of
ContentRefDeserializer::deserialize_newtype_struct</li>
<li>Additional commits viewable in <a
href="https://github.com/serde-rs/serde/compare/v1.0.204...v1.0.209">compare
view</a></li>
</ul>
</details>
<br />


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rust/Cargo.lock

@@ -5301,9 +5301,9 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.204"
+version = "1.0.209"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bc76f558e0cbb2a839d37354c575f1dc3fdc6546b5be373ba43d95f231bf7c12"
+checksum = "99fce0ffe7310761ca6bf9faf5115afbc19688edd00171d81b1bb1b116c63e09"
 dependencies = [
  "serde_derive",
 ]
@@ -5319,9 +5319,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.204"
+version = "1.0.209"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0cd7e117be63d3c3678776753929474f3b04a43a080c744d6b0ae2a8c28e222"
+checksum = "a5831b979fd7b5439637af1752d535ff49f4860c0f341d1baeb6faf0f4242170"
 dependencies = [
  "proc-macro2",
  "quote",

rust/headless-client/Cargo.toml

@@ -21,7 +21,7 @@ ip_network = { version = "0.4", default-features = false }
 phoenix-channel = { workspace = true }
 rustls = { workspace = true }
 secrecy = { workspace = true }
-serde = { version = "1.0.204", features = ["derive"] }
+serde = { version = "1.0.209", features = ["derive"] }
 serde_json = "1.0.125"
 thiserror = { version = "1.0", default-features = false }
 # This actually relies on many other features in Tokio, so this will probably

rust/phoenix-channel/Cargo.toml

@@ -12,7 +12,7 @@ hex = "0.4"
 libc = "0.2"
 rand_core = "0.6.4"
 secrecy = { workspace = true }
-serde = { version = "1.0.204", features = ["derive"] }
+serde = { version = "1.0.209", features = ["derive"] }
 serde_json = "1.0.125"
 sha2 = "0.10.8"
 socket-factory = { workspace = true }

rust/relay/Cargo.toml

@@ -25,7 +25,7 @@ proptest = { version = "1", optional = true }
 rand = "0.8.5"
 rustls = { workspace = true }
 secrecy = { workspace = true }
-serde = { version = "1.0.204", features = ["derive"] }
+serde = { version = "1.0.209", features = ["derive"] }
 sha2 = "0.10.8"
 smallvec = "1.13.2"
 socket-factory = { workspace = true }