chore(deps): update determinatesystems/nix-installer-action action to v18 (#103)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[DeterminateSystems/nix-installer-action](https://redirect.github.com/DeterminateSystems/nix-installer-action)
| action | major | `v17` -> `v18` |

---

### Release Notes

<details>
<summary>DeterminateSystems/nix-installer-action
(DeterminateSystems/nix-installer-action)</summary>

###
[`v18`](https://redirect.github.com/DeterminateSystems/nix-installer-action/releases/tag/v18)

[Compare
Source](https://redirect.github.com/DeterminateSystems/nix-installer-action/compare/v17...v18)

##### What's Changed

- Correctly suppress empty summaries by
[@&#8203;gustavderdrache](https://redirect.github.com/gustavderdrache)
in
[https://github.com/DeterminateSystems/nix-installer-action/pull/171](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/171)
- Test penance by
[@&#8203;gustavderdrache](https://redirect.github.com/gustavderdrache)
in
[https://github.com/DeterminateSystems/nix-installer-action/pull/172](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/172)
- Add hash mismatches to summary by
[@&#8203;gustavderdrache](https://redirect.github.com/gustavderdrache)
in
[https://github.com/DeterminateSystems/nix-installer-action/pull/173](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/173)
- Fix an obscure error case where if the only log fails, the rendering
is wack by [@&#8203;grahamc](https://redirect.github.com/grahamc) in
[https://github.com/DeterminateSystems/nix-installer-action/pull/177](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/177)
- Ditch the docker shim in favor of a double fork by
[@&#8203;grahamc](https://redirect.github.com/grahamc) in
[https://github.com/DeterminateSystems/nix-installer-action/pull/180](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/180)
- Add a note about pinning by
[@&#8203;grahamc](https://redirect.github.com/grahamc) in
[https://github.com/DeterminateSystems/nix-installer-action/pull/182](https://redirect.github.com/DeterminateSystems/nix-installer-action/pull/182)

**Full Changelog**:
https://github.com/DeterminateSystems/nix-installer-action/compare/v17...v18

</details>

---

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---

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---

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.github/workflows/update-flake.yaml

@@ -22,7 +22,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Install Nix
-        uses: DeterminateSystems/nix-installer-action@v17
+        uses: DeterminateSystems/nix-installer-action@v18
 
       - name: Check for Updates
         id: check_updates
@@ -74,7 +74,7 @@ jobs:
           ref: update_flake_lock_action
 
       - name: Install Nix
-        uses: DeterminateSystems/nix-installer-action@v17
+        uses: DeterminateSystems/nix-installer-action@v18
 
       - name: Build and Test Configuration
         id: build