fix coding norm check in hosts.py (#1174)

`pynorms` test is trapping a error in `hosts.py` on the conditional for singularity container that is now fixed.

Also start ignoring git hidden directories from pynorms.

.github/workflows/pynorms.yaml

@@ -21,4 +21,4 @@ jobs:
     - name: Run pycodestyle
       run: |
         cd $GITHUB_WORKSPACE/global-workflow
-        pycodestyle -v --config ./.pycodestyle .
+        pycodestyle -v --config ./.pycodestyle --exclude='.git,.github' ./

workflow/hosts.py

@@ -32,7 +32,7 @@ def __init__(self, host=None):
     def detect(cls):
 
         machine = 'NOTFOUND'
-        container = os.getenv('SINGULARITY_NAME')
+        container = os.getenv('SINGULARITY_NAME', None)
 
         if os.path.exists('/scratch1/NCEPDEV'):
             machine = 'HERA'
@@ -44,7 +44,7 @@ def detect(cls):
             machine = 'WCOSS2'
         elif os.path.exists('/data/prod'):
             machine = 'S4'
-        elif container != None:
+        elif container is not None:
             machine = 'CONTAINER'
 
         if machine not in Host.SUPPORTED_HOSTS: