Update actions/setup-dotnet action to v3

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/setup-dotnet	action	major	v2 -> v3

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Release Notes

actions/setup-dotnet

### [`v3`](https://togithub.com/actions/setup-dotnet/compare/v2...v3) [Compare Source](https://togithub.com/actions/setup-dotnet/compare/v2...v3)

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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.

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• [ ] If you want to rebase/retry this PR, click this checkbox.

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[codecov-commenter]

Codecov Report

Merging #420 (097f167) into master (f867372) will decrease coverage by 0.60%. The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #420      +/-   ##
==========================================
- Coverage   83.98%   83.37%   -0.61%     
==========================================
  Files          51       51              
  Lines        2809     2809              
  Branches      310      310              
==========================================
- Hits         2359     2342      -17     
- Misses        331      349      +18     
+ Partials      119      118       -1     

Impacted Files	Coverage Δ
SharpPcap/LibPcap/WindowsNativeMethods.cs	0.00% <0.00%> (-40.00%)	:arrow_down:
SharpPcap/LibPcap/PcapInterface.cs	86.06% <0.00%> (-2.43%)	:arrow_down:
SharpPcap/LibPcap/PcapDevice.cs	76.11% <0.00%> (-1.50%)	:arrow_down:
SharpPcap/WinpkFilter/WinpkFilterDevice.cs	82.75% <0.00%> (-1.38%)	:arrow_down:
SharpPcap/LibPcap/LibPcapLiveDevice.cs	80.31% <0.00%> (ø)

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