island: Remove server_config.json.develop

Since Monkey Island no longer writes to server_config.json in the source
code directory, and each package will overwrite server_config.json with
its own server config (until we separate the deployment from the config
in issue #1205), we no longer need server_config.json.develop and we
don't need to worry about accidentally committing credentials to git.

.travis.yml

@@ -21,9 +21,6 @@ python:
 
 os: linux
 
-before_install:
-# Init server_config.json to default
-- cp monkey/monkey_island/cc/server_config.json.develop monkey/monkey_island/cc/server_config.json
 
 install:
 # Python

monkey/monkey_island/cc/server_utils/consts.py

@@ -40,9 +40,5 @@ DEFAULT_SERVER_CONFIG_PATH = os.path.expandvars(
     os.path.join(MONKEY_ISLAND_ABS_PATH, "cc", SERVER_CONFIG_FILENAME)
 )
 
-DEFAULT_DEVELOP_SERVER_CONFIG_PATH = os.path.join(
-    MONKEY_ISLAND_ABS_PATH, "cc", f"{SERVER_CONFIG_FILENAME}.develop"
-)
-
 DEFAULT_LOG_LEVEL = "INFO"
 DEFAULT_START_MONGO_DB = True