chore(deps): update go toolchain directive to v1.26.3 (#763)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [go](https://go.dev/)
([source](https://redirect.github.com/golang/go)) | toolchain | patch |
`1.26.2` → `1.26.3` |
| [go](https://redirect.github.com/actions/go-versions) | uses-with |
patch | `1.26.2` → `1.26.3` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the [Dependency
Dashboard](../issues/4) for more information.

---

### Release Notes

<details>
<summary>golang/go (go)</summary>

###
[`v1.26.3`](https://redirect.github.com/golang/go/compare/go1.26.2...go1.26.3)

</details>

<details>
<summary>actions/go-versions (go)</summary>

###
[`v1.26.3`](https://redirect.github.com/actions/go-versions/releases/tag/1.26.3-25533533231):
1.26.3

[Compare
Source](https://redirect.github.com/actions/go-versions/compare/1.26.2-24114135105...1.26.3-25533533231)

Go 1.26.3

</details>

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Author: bootjp

.github/workflows/jepsen.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v6
         with:
-          go-version: "1.26.2"
+          go-version: "1.26.3"
 
       - name: Bring up Jepsen VMs
         working-directory: jepsen

go.mod

@@ -2,7 +2,7 @@ module github.com/bootjp/elastickv
 
 go 1.25.0
 
-toolchain go1.26.2
+toolchain go1.26.3
 
 require (
 	github.com/Jille/grpc-multi-resolver v1.3.0