[fix] utils/build_env.py: make sure to always use searx/settings.yml

ignore SEARX_SETTINGS_PATH

[1] https://github.com/searx/searx/pull/2408#pullrequestreview-565247895

Suggested-by: @dalf [1]
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

utils/build_env.py

@@ -4,10 +4,17 @@
 
 # set path
 import sys
-from os.path import realpath, dirname, join, sep
+import os
+from os.path import realpath, dirname, join, sep, abspath
+
 repo_root = realpath(dirname(realpath(__file__)) + sep + '..')
 sys.path.insert(0, repo_root)
 
+# Under the assumption that a brand is always a fork assure that the settings
+# file from reposetorie's working tree is used to generate the build_env, not
+# from /etc/searx/settings.yml.
+os.environ['SEARX_SETTINGS_PATH'] = abspath(dirname(__file__) + sep + 'settings.yml')
+
 from searx import brand
 
 name_val = [