Build sherpa-onnx as a single shared library (#1078)

When `-D BUILD_SHARED_LIBS=ON` is passed to `cmake`, it builds a single shared library.

Specifically, 

- For C APIs, it builds `libsherpa-onnx-c-api.so`
- For Python APIs, it builds `_sherpa_onnx.cpython-xx-xx.so`
- For Kotlin and Java APIs, it builds `libsherpa-onnx-jni.so`

There is no `libsherpa-onnx-core.so` any longer.

Note it affects only shared libraries.

scripts/go/_internal/build_darwin_amd64.go

@@ -2,5 +2,5 @@
 
 package sherpa_onnx
 
-// #cgo LDFLAGS: -L ${SRCDIR}/lib/x86_64-apple-darwin -lsherpa-onnx-c-api -lsherpa-onnx-core -lkaldi-native-fbank-core  -lkaldi-decoder-core -lsherpa-onnx-kaldifst-core -lsherpa-onnx-fstfar -lsherpa-onnx-fst -lpiper_phonemize -lespeak-ng -lucd -lonnxruntime -lssentencepiece_core -Wl,-rpath,${SRCDIR}/lib/x86_64-apple-darwin
+// #cgo LDFLAGS: -L ${SRCDIR}/lib/x86_64-apple-darwin -lsherpa-onnx-c-api -lonnxruntime -Wl,-rpath,${SRCDIR}/lib/x86_64-apple-darwin
 import "C"