State monthly means in repo name

ERAIN_SFC12_MM/meta.yaml

-repo_name: ERAIN_SFC12
+repo_name: ERAIN_SFC12_MM
 
 people:  Willi Rath (<wrath@geomar.de>)
 
-http_path_remote: https://git.geomar.de/data/ERAIN_SFC12
+http_path_remote: https://git.geomar.de/data/ERAIN_SFC12_MM
 
-git_path_remote: git@git.geomar.de:data/ERAIN_SFC12
+git_path_remote: git@git.geomar.de:data/ERAIN_SFC12_MM
 
 repo_description: |
     ERA-Interim surface 12_MM