reorganize tests directory (#3196)

```
- source
  - tests
     - common
     - tf
     - pt
```

---------

Signed-off-by: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>

Author: njzjz

pyproject.toml

@@ -130,7 +130,7 @@ test-command = [
     "python -m deepmd -h",
     "dp -h",
     "dp_ipi",
-    "pytest {project}/source/tests/test_lammps.py"
+    "pytest {project}/source/tests/tf/test_lammps.py"
 ]
 test-extras = ["cpu", "test", "lmp", "ipi"]
 build = ["cp310-*"]

source/tests/__init__.py

@@ -0,0 +1 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later

source/tests/common/__init__.py

@@ -0,0 +1 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later

source/tests/common/common.py

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later
+import pathlib
+
+tests_path = pathlib.Path(__file__).parent.absolute()
+infer_path = (tests_path.parent / "infer").absolute()

source/tests/test_argument_parser.py …rce/tests/common/test_argument_parser.pysource/tests/test_argument_parser.py renamed to source/tests/common/test_argument_parser.py source/tests/test_argument_parser.py renamed to source/tests/common/test_argument_parser.py

@@ -21,7 +21,7 @@
     Union,
 )
 
-from deepmd.tf.entrypoints.main import (
+from deepmd.main import (
     get_ll,
     parse_args,
 )

source/tests/test_examples.py source/tests/common/test_examples.pysource/tests/test_examples.py renamed to source/tests/common/test_examples.py

@@ -7,14 +7,14 @@
     Path,
 )
 
-from deepmd.tf.common import (
+from deepmd.common import (
     j_loader,
 )
-from deepmd.tf.utils.argcheck import (
+from deepmd.utils.argcheck import (
     normalize,
 )
 
-p_examples = Path(__file__).parent.parent.parent / "examples"
+p_examples = Path(__file__).parent.parent.parent.parent / "examples"
 
 input_files = (
     p_examples / "water" / "se_e2_a" / "input.json",

source/tests/test_gui.py source/tests/common/test_gui.pysource/tests/test_gui.py renamed to source/tests/common/test_gui.py

@@ -3,7 +3,7 @@
 
 import numpy as np
 
-from deepmd.tf.common import (
+from deepmd.common import (
     select_idx_map,
 )