Make pyproject.toml PEP 621 compliant

- converted tool.poetry to PEP 621 (default behavior for poetry)
- converted setup.py to PEP 621 (recommended by setuptools)
- use pyproject.toml instead of version.txt
- use importlib instead of version.txt
- use PEP 621 dependency format in flatpak build scripts
- added tomli as a dev dependency (used in build scripts)
- removed version.txt (no longer used)
- cleaned up dependencies

- version is still in desktop/setup.py (unclear on how snapcraft uses it)
- poetry lockfiles need to be rebuilt

desktop/scripts/build-macos.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 import os
+import sys
 import inspect
 import click
 import platform
@@ -8,6 +9,11 @@ import shutil
 import glob
 import itertools
 
+if sys.version_info >= (3, 11):
+    import tomllib
+else:
+    import tomli as tomllib
+
 from common import get_binary_arches
 
 root = os.path.dirname(
@@ -270,9 +276,10 @@ def package(app_path):
         return
 
     print("> Create DMG")
-    version_filename = f"{root}/cli/onionshare_cli/resources/version.txt"
-    with open(version_filename) as f:
-        version = f.read().strip()
+    pyproject_filename = f"{root}/cli/pyproject.toml"
+    with open(pyproject_filename, "rb") as f:
+        pyproject = tomllib.load(f)
+        version = pyproject['project']['version']
 
     os.makedirs(f"{desktop_dir}/dist", exist_ok=True)
     dmg_path = f"{desktop_dir}/dist/OnionShare-{version}.dmg"