chore(deps): update helm/chart-testing-action action to v2.8.0 (#1990)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[helm/chart-testing-action](https://redirect.github.com/helm/chart-testing-action)
| action | minor | `v2.7.0` -> `v2.8.0` |

---

### Release Notes

<details>
<summary>helm/chart-testing-action (helm/chart-testing-action)</summary>

###
[`v2.8.0`](https://redirect.github.com/helm/chart-testing-action/releases/tag/v2.8.0)

[Compare
Source](https://redirect.github.com/helm/chart-testing-action/compare/v2.7.0...v2.8.0)

#### What's Changed

- Bump the actions group across 1 directory with 4 updates by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;171](https://redirect.github.com/helm/chart-testing-action/pull/171)
- Fix the broken link for GitHub Help Documentation by
[@&#8203;subramani95](https://redirect.github.com/subramani95) in
[#&#8203;174](https://redirect.github.com/helm/chart-testing-action/pull/174)
- bump ct and yamale version by
[@&#8203;cpanato](https://redirect.github.com/cpanato) in
[#&#8203;178](https://redirect.github.com/helm/chart-testing-action/pull/178)
- Bump actions/checkout from 4.2.2 to 5.0.0 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;181](https://redirect.github.com/helm/chart-testing-action/pull/181)
- Bump actions/setup-python from 5.4.0 to 6.0.0 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;179](https://redirect.github.com/helm/chart-testing-action/pull/179)
- Bump the actions group across 1 directory with 2 updates by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;183](https://redirect.github.com/helm/chart-testing-action/pull/183)
- Use uv instead of python venv by
[@&#8203;nikolaik](https://redirect.github.com/nikolaik) in
[#&#8203;172](https://redirect.github.com/helm/chart-testing-action/pull/172)
- Bump sigstore/cosign-installer from 3.8.1 to 4.0.0 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;184](https://redirect.github.com/helm/chart-testing-action/pull/184)

#### New Contributors

- [@&#8203;subramani95](https://redirect.github.com/subramani95) made
their first contribution in
[#&#8203;174](https://redirect.github.com/helm/chart-testing-action/pull/174)
- [@&#8203;nikolaik](https://redirect.github.com/nikolaik) made their
first contribution in
[#&#8203;172](https://redirect.github.com/helm/chart-testing-action/pull/172)

**Full Changelog**:
<helm/chart-testing-action@v2...v2.8.0>

</details>

---

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---

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---

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.github/workflows/lint_test_charts.yaml

@@ -29,7 +29,7 @@ jobs:
           fetch-depth: 0
 
       - uses: actions/setup-python@v5
-      - uses: helm/chart-testing-action@v2.7.0
+      - uses: helm/chart-testing-action@v2.8.0
       - uses: azure/setup-helm@v4
         with:
           version: 'v3.2.0'
@@ -73,7 +73,7 @@ jobs:
           fetch-depth: 0
 
       - uses: actions/setup-python@v5
-      - uses: helm/chart-testing-action@v2.7.0
+      - uses: helm/chart-testing-action@v2.8.0
       - uses: azure/setup-helm@v4
         with:
           version: 'v3.2.0'