chore(deps): bump capnp from 0.25.5 to 0.26.0 (#269)

Bumps [capnp](https://github.com/capnproto/capnproto-rust) from 0.25.5
to 0.26.0.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/de193c788399f1fb3d8909cdf930e359bb87fa87"><code>de193c7</code></a>
prepare for v0.26.0 release</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/20bff6357990d7d1d548a56c34b27f5c649b946a"><code>20bff63</code></a>
update rand deps in examples</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/9759b10fa212dcddec54b4e4670d067cbd776e39"><code>9759b10</code></a>
Use NonNull in Allocator</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/a9f96530df695fa7c4451fa225e99d1a2ea290fb"><code>a9f9653</code></a>
Use GeneratedCodeArena to avoid the need for unsafe{} in RawEnumSchema
constr...</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/a431ce518e62a9cd0871c9437d286698a4a8e1c2"><code>a431ce5</code></a>
bump to version 0.26.0-alpha</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/0f9a5b1604b9a64f7e4a5a1dcba63fe882501996"><code>0f9a5b1</code></a>
fix formatting</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/55857815f83a94cab620d547cc13cea53e0a1ac5"><code>5585781</code></a>
update changelog</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/64c1e12cd39e8086cb33b88adb0a81d8179c5c33"><code>64c1e12</code></a>
fix another possible instance of undefined behavior</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/648dcabdaadd1bf57ee4c2eeda510e72c366cbb5"><code>648dcab</code></a>
prepare for capnp-v0.25.6 release</li>
<li><a
href="https://github.com/capnproto/capnproto-rust/commit/fc5eefb714e332c6c43c9d37cecb21378ca48d4f"><code>fc5eefb</code></a>
use wrapping_add() instead of add() to avoid undefined behavior in
follow_far...</li>
<li>Additional commits viewable in <a
href="https://github.com/capnproto/capnproto-rust/compare/capnp-v0.25.5...capnp-v0.26.0">compare
view</a></li>
</ul>
</details>
<br />

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Author: dependabot[bot]

Cargo.lock

@@ -11,7 +11,7 @@ repository  = "https://github.com/hyperpolymath/echidna"
 build       = "build.rs"
 
 [dependencies]
-capnp = "0.25"
+capnp = "0.26"
 
 [build-dependencies]
 capnpc = "0.25"