Update actions/setup-dotnet action to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/setup-dotnet	action	major	v3 -> v4

---

Release Notes

actions/setup-dotnet (actions/setup-dotnet)

### [`v4`](https://togithub.com/actions/setup-dotnet/compare/v3...v4) [Compare Source](https://togithub.com/actions/setup-dotnet/compare/v3...v4)

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR has been generated by Mend Renovate. View repository job log here.

[codecov[bot]]

Codecov Report

Merging #139 (f2bfbb8) into master (9450a47) will not change coverage. The diff coverage is n/a.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #139 +/- ## ======================================= Coverage 77.74% 77.74% ======================================= Files 9 9 Lines 692 692 Branches 41 41 ======================================= Hits 538 538 Misses 127 127 Partials 27 27 ```