test: use attr for version instead of regex

Signed-off-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

Author: kbdharun

pyproject.toml

@@ -73,7 +73,7 @@ Funding = "https://liberapay.com/tldr-pages"
 
 [tool.hatch.version]
 path = "tldr.py"
-pattern = '''__version__ = ["'](.*?)["']'''
+attr = "__version__"
 
 [tool.hatch.build.targets.wheel.shared-data]
 "docs/man" = "share/man/man1"