update version discovery

src/gphotos_sync/__init__.py

@@ -1,14 +1,6 @@
-try:
-    # Use live version from git
-    from setuptools_scm import get_version
+from importlib.metadata import version  # noqa
 
-    # Warning: If the install is nested to the same depth, this will always succeed
-    tmp_version = get_version(root="../../", relative_to=__file__)
-    del get_version
-except (ImportError, LookupError):
-    # Use installed version
-    from ._version import version as __version__
-else:
-    __version__ = tmp_version
+__version__ = version("gphotos-sync")
+del version
 
 __all__ = ["__version__"]