Add keyword spotting for C# #1199

Job	Run time
ubuntu-20.04 3.10 transducer	7m 22s
ubuntu-20.04 3.10 paraformer	8m 0s
ubuntu-20.04 3.10 zipformer2-ctc	8m 12s
ubuntu-22.04 3.10 transducer	7m 9s
ubuntu-22.04 3.10 paraformer	10m 26s
ubuntu-22.04 3.10 zipformer2-ctc	7m 28s
windows-latest 3.10 transducer	22m 25s
windows-latest 3.10 paraformer	21m 17s
windows-latest 3.10 zipformer2-ctc	13m 2s
macos-latest 3.10 transducer	5m 17s
macos-latest 3.10 paraformer	7m 27s
macos-latest 3.10 zipformer2-ctc	6m 46s
macos-14 3.10 transducer	5m 13s
macos-14 3.10 paraformer	7m 26s
macos-14 3.10 zipformer2-ctc	5m 2s
	2h 22m 32s

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