Fix parsing of smartcardoptions config

With the previous code, a trailing newline would result in an empty
space being part of the list. When this is passed to keytool, it fails
with "Illegal option: ".

Instead of doing overly complicated regex based string substitution
followed by parametrized splitting, we can simply use `.split()`
without any parameters, and Python will automatically strip any
whitespace.

fdroidserver/common.py

@@ -385,7 +385,8 @@ def read_config(opts=None):
     # smartcardoptions must be a list since its command line args for Popen
     smartcardoptions = config.get('smartcardoptions')
     if isinstance(smartcardoptions, str):
-        config['smartcardoptions'] = re.sub(r'\s+', r' ', config['smartcardoptions']).split(' ')
+        options = re.sub(r'\s+', r' ', config['smartcardoptions']).split(' ')
+        config['smartcardoptions'] = [i.strip() for i in options if i]
     elif not smartcardoptions and 'keystore' in config and config['keystore'] == 'NONE':
         # keystore='NONE' means use smartcard, these are required defaults
         config['smartcardoptions'] = ['-storetype', 'PKCS11', '-providerName',