Improve: Changed PyTorch to an optional dependency when used style_bert_vits2 as a library

ONNXRuntime has relied on CUDA 12.x / cuDNN 9.x by default since v1.19.0, while PyTorch finally supports cuDNN 9 since v2.4.0.
Therefore, unless the pinning of torch<2.4 is eliminated, CUDA cannot be used with the latest version of ONNXRuntime.

pyproject.toml

@@ -22,7 +22,6 @@ classifiers = [
     "Programming Language :: Python :: Implementation :: CPython",
 ]
 dependencies = [
-    "accelerate",
     "cmudict",
     "cn2an",
     "g2p_en",
@@ -37,10 +36,15 @@ dependencies = [
     "pypinyin",
     "pyworld-prebuilt",
     "safetensors",
-    "torch>=2.1",
     "transformers",
 ]
 
+[project.optional-dependencies]
+torch = [
+    "accelerate",
+    "torch>=2.1",
+]
+
 [project.urls]
 Documentation = "https://github.com/litagin02/Style-Bert-VITS2#readme"
 Issues = "https://github.com/litagin02/Style-Bert-VITS2/issues"
@@ -68,6 +72,7 @@ packages = ["style_bert_vits2"]
 
 [tool.hatch.envs.test]
 dependencies = ["coverage[toml]>=6.5", "pytest", "scipy"]
+features = ["torch"]
 [tool.hatch.envs.test.scripts]
 # Usage: `hatch run test:test`
 test = "pytest {args:tests}"
@@ -77,6 +82,8 @@ test-cov = "coverage run -m pytest {args:tests}"
 cov-report = ["- coverage combine", "coverage report"]
 # Usage: `hatch run test:cov`
 cov = ["test-cov", "cov-report"]
+[[tool.hatch.envs.test.matrix]]
+python = ["3.9", "3.10", "3.11"]
 
 [tool.hatch.envs.style]
 detached = true
@@ -94,9 +101,6 @@ fmt = [
     "check",
 ]
 
-[[tool.hatch.envs.test.matrix]]
-python = ["3.9", "3.10", "3.11"]
-
 [tool.coverage.run]
 source_pkgs = ["style_bert_vits2", "tests"]
 branch = true