c#: Bump dotnet version for tests #2653

Job	Run time
Check	2m 7s
Rustfmt	11s
Build wit-bindgen (x86_64-linux, ubuntu-latest)	1m 45s
Test (ubuntu-latest, c)	4m 27s
Build wit-bindgen (x86_64-macos, macos-latest, x86_64-apple-darwin)	1m 46s
Test (ubuntu-latest, rust)	5m 2s
Build wit-bindgen (aarch64-macos, macos-latest, aarch64-apple-darwin)	1m 22s
Crate Unit Tests	1m 7s
Test (ubuntu-latest, teavm-java)	5m 15s
Build wit-bindgen (x86_64-windows, windows-latest)	3m 6s
Test (ubuntu-latest, go)	6m 3s
verify-publish	1m 56s
Build wit-bindgen (aarch64-linux, ubuntu-latest, aarch64-unknown-linux-gnu)	1m 51s
Test (ubuntu-latest, csharp)	4m 48s
Test (macos-latest, c)	5m 20s
Test (macos-latest, rust)	4m 30s
Test (macos-latest, teavm-java)	5m 34s
Test (macos-latest, go)	5m 31s
Test (macos-latest, csharp)	7m 8s
Test (windows-latest, c)	9m 19s
Test (windows-latest, rust)	10m 12s
Test (windows-latest, teavm-java)	9m 6s
Test (windows-latest, go)	10m 57s
Test (windows-latest, csharp)	34m 47s
Record the result of testing and building steps	1s
	2h 23m 11s

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