fix(linux): Fix attribute error

Newer versions of requests-cache (>= 0.6) restructure some code so
that the _core_ namespace is no longer available. However, it turns
out that we don't need to specify that namespace at all, so this
change will work with both older and newer versions of
requests-cache.

This will fix #6085.

linux/keyman-config/keyman_config/get_kmp.py

@@ -43,7 +43,7 @@ def get_package_download_data(packageID, weekCache=False):
     response = requests.get(api_url)
     logging.debug('Time: {0} / Used Cache: {1}'.format(now, response.from_cache))
     os.chdir(current_dir)
-    requests_cache.core.uninstall_cache()
+    requests_cache.uninstall_cache()
     if response.status_code == 200:
         return response.json()
     else:
@@ -75,7 +75,7 @@ def get_keyboard_data(keyboardID, weekCache=False):
     response = requests.get(api_url)
     logging.debug('Time: {0} / Used Cache: {1}'.format(now, response.from_cache))
     os.chdir(current_dir)
-    requests_cache.core.uninstall_cache()
+    requests_cache.uninstall_cache()
     if response.status_code == 200:
         return response.json()
     else:
@@ -203,7 +203,7 @@ def download_kmp_file(url, kmpfile, cache=False):
     if cache:
         logging.debug('Time: {0} / Used Cache: {1}'.format(now, response.from_cache))
         os.chdir(current_dir)
-        requests_cache.core.uninstall_cache()
+        requests_cache.uninstall_cache()
 
     if response.status_code == 200:
         with open(kmpfile, 'wb') as f: