build(deps): bump actions-rust-lang/setup-rust-toolchain from 1.15.3 to 1.15.4 (#1101)

Bumps
[actions-rust-lang/setup-rust-toolchain](https://github.com/actions-rust-lang/setup-rust-toolchain)
from 1.15.3 to 1.15.4.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/releases">actions-rust-lang/setup-rust-toolchain's
releases</a>.</em></p>
<blockquote>
<h2>v1.15.4</h2>
<h2>What's Changed</h2>
<ul>
<li>Bump Swatinem/rust-cache from 2.8.2 to 2.9.1 by <a
href="https://github.com/hyperfinitism"><code>@​hyperfinitism</code></a>
in <a
href="https://redirect.github.com/actions-rust-lang/setup-rust-toolchain/pull/87">actions-rust-lang/setup-rust-toolchain#87</a></li>
</ul>
<h2>New Contributors</h2>
<ul>
<li><a
href="https://github.com/hyperfinitism"><code>@​hyperfinitism</code></a>
made their first contribution in <a
href="https://redirect.github.com/actions-rust-lang/setup-rust-toolchain/pull/87">actions-rust-lang/setup-rust-toolchain#87</a></li>
</ul>
<p><strong>Full Changelog</strong>: <a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/compare/v1.15.3...v1.15.4">https://github.com/actions-rust-lang/setup-rust-toolchain/compare/v1.15.3...v1.15.4</a></p>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/blob/main/CHANGELOG.md">actions-rust-lang/setup-rust-toolchain's
changelog</a>.</em></p>
<blockquote>
<h2>[1.15.4] - 2026-03-15</h2>
<ul>
<li>Bump Swatinem/rust-cache from 2.8.2 to 2.9.1 (<a
href="https://redirect.github.com/actions-rust-lang/setup-rust-toolchain/issues/87">#87</a>
by <a
href="https://github.com/hyperfinitism"><code>@​hyperfinitism</code></a>)
This gets rid of the warnings about Node.js 20.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/commit/150fca883cd4034361b621bd4e6a9d34e5143606"><code>150fca8</code></a>
Update CHANGELOG for version 1.15.4</li>
<li><a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/commit/aa63f5758dc452b0530bfc21a02832b8f64f2239"><code>aa63f57</code></a>
Merge pull request <a
href="https://redirect.github.com/actions-rust-lang/setup-rust-toolchain/issues/87">#87</a>
from hyperfinitism/deps/bump-rust-cache</li>
<li><a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/commit/229ed076e84b5b65cd2f9d73f942027b40c35131"><code>229ed07</code></a>
deps: Bump Swatinem/rust-cache from 2.8.2 to 2.9.1</li>
<li>See full diff in <a
href="https://github.com/actions-rust-lang/setup-rust-toolchain/compare/v1.15.3...v1.15.4">compare
view</a></li>
</ul>
</details>
<br />


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.github/workflows/rs_ci.yml

@@ -44,7 +44,7 @@ jobs:
           unzip "protoc-${{ env.PB_VERSION }}-${{ env.PB_TARGET }}.zip" -d "$HOME/.local"
           export PATH="$PATH:$HOME/.local/bin"
 
-      - uses: actions-rust-lang/setup-rust-toolchain@a0b538fa0b742a6aa35d6e2c169b4bd06d225a98 # v1.15.3
+      - uses: actions-rust-lang/setup-rust-toolchain@150fca883cd4034361b621bd4e6a9d34e5143606 # v1.15.4
         with:
           cache: false
       - uses: mozilla-actions/sccache-action@7d986dd989559c6ecdb630a3fd2557667be217ad # v0.0.9
@@ -72,7 +72,7 @@ jobs:
           unzip "protoc-${{ env.PB_VERSION }}-${{ env.PB_TARGET }}.zip" -d "$HOME/.local"
           export PATH="$PATH:$HOME/.local/bin"
 
-      - uses: actions-rust-lang/setup-rust-toolchain@a0b538fa0b742a6aa35d6e2c169b4bd06d225a98 # v1.15.3
+      - uses: actions-rust-lang/setup-rust-toolchain@150fca883cd4034361b621bd4e6a9d34e5143606 # v1.15.4
         with:
           components: clippy
           cache: false
@@ -104,7 +104,7 @@ jobs:
           unzip "protoc-${{ env.PB_VERSION }}-${{ env.PB_TARGET }}.zip" -d "$HOME/.local"
           export PATH="$PATH:$HOME/.local/bin"
 
-      - uses: actions-rust-lang/setup-rust-toolchain@a0b538fa0b742a6aa35d6e2c169b4bd06d225a98 # v1.15.3
+      - uses: actions-rust-lang/setup-rust-toolchain@150fca883cd4034361b621bd4e6a9d34e5143606 # v1.15.4
         with:
           cache: false
       - uses: mozilla-actions/sccache-action@7d986dd989559c6ecdb630a3fd2557667be217ad # v0.0.9
@@ -132,7 +132,7 @@ jobs:
           unzip "protoc-${{ env.PB_VERSION }}-${{ env.PB_TARGET }}.zip" -d "$HOME/.local"
           export PATH="$PATH:$HOME/.local/bin"
 
-      - uses: actions-rust-lang/setup-rust-toolchain@a0b538fa0b742a6aa35d6e2c169b4bd06d225a98 # v1.15.3
+      - uses: actions-rust-lang/setup-rust-toolchain@150fca883cd4034361b621bd4e6a9d34e5143606 # v1.15.4
         with:
           cache: false
       - uses: taiki-e/install-action@cbb1dcaa26e1459e2876c39f61c1e22a1258aac5 # v2.68.33
@@ -150,7 +150,7 @@ jobs:
         os: [ubuntu-22.04, macos-latest]
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-      - uses: actions-rust-lang/setup-rust-toolchain@a0b538fa0b742a6aa35d6e2c169b4bd06d225a98 # v1.15.3
+      - uses: actions-rust-lang/setup-rust-toolchain@150fca883cd4034361b621bd4e6a9d34e5143606 # v1.15.4
         with:
           components: rustfmt
           cache: false