[fix] #113: Support libnacl version from v1.7.2

Change libnacl version
Force libnacl minimum version to v1.7.2

To support Py3.9
https://github.com/saltstack/libnacl/issues/120#issuecomment-721336469
https://github.com/saltstack/libnacl/commit/33b22d2edc86edbb1a2dcb0b902428a40cc5e35b

duniterpy/key/ascii_armor.py

 import base64
 import libnacl
+from libnacl.version import version as libnacl_version
 import re
 from typing import Optional, List, Dict, Any
 
@@ -14,7 +15,7 @@ HEADER_PREFIX = "-----"
 DASH_ESCAPE_PREFIX = "\x2D\x20"
 
 # Version field value
-VERSION_FIELD_VALUE = "Python Libnacl " + libnacl.__version__
+VERSION_FIELD_VALUE = "Python Libnacl " + libnacl_version
 
 # Parser cursor status
 ON_MESSAGE_FIELDS = 1

pyproject.toml

@@ -31,7 +31,7 @@ pypeg2 = "^2.15.2"
 attrs = "^19.3.0"
 base58 = "^2.0.0"
 pylibscrypt = "^1.8.0"
-libnacl = "^1.6.1"
+libnacl = "^1.7.2"
 pyaes = "^1.6.1"
 
 [tool.poetry.dev-dependencies]