L2SS-871: use env variable to determine path

tangostationcontrol/tangostationcontrol/statistics/writer/hdf5.py

@@ -36,14 +36,15 @@ __all__ = [
 
 def _get_lsc_version() -> str:
     """ Retrieve the Lofar Station Control software version """
-    filepath = f"{os.path.expanduser('~')}/tangostationcontrol/VERSION"
+    filepath = os.path.join(os.environ.get('LOFAR20_DIR'), 'tangostationcontrol/VERSION')
     with open(filepath) as f:
         version = f.readline().strip()
     return version or ""
 
 def _get_writer_version() -> str:
     """ Retrieve the Statistics Writer software version """
-    with open('VERSION') as f:
+    filepath = os.path.join(os.path.dirname(__file__), '/VERSION')
+    with open(filepath) as f:
         version = f.readline().strip()
     return version or ""