Prefer readthedocs.io instead of readthedocs.org for doc links (#41537)

Read the Docs moved hosting to readthedocs.io instead of
readthedocs.org. Fix all links in the project.

For additional details, see:

https://blog.readthedocs.com/securing-subdomains/

> Starting today, Read the Docs will start hosting projects from
> subdomains on the domain readthedocs.io, instead of on
> readthedocs.org. This change addresses some security concerns around
> site cookies while hosting user generated data on the same domain as
> our dashboard.

lib/ansible/plugins/lookup/consul_kv.py

@@ -13,7 +13,7 @@ DOCUMENTATION = """
         Values can be easily set in the kv store with simple rest commands
       - C(curl -X PUT -d 'some-value' http://localhost:8500/v1/kv/ansible/somedata)
     requirements:
-      - 'python-consul python library U(http://python-consul.readthedocs.org/en/latest/#installation)'
+      - 'python-consul python library U(https://python-consul.readthedocs.io/en/latest/#installation)'
     options:
       _raw:
         description: List of key(s) to retrieve.
@@ -84,7 +84,7 @@ class LookupModule(LookupBase):
     def run(self, terms, variables=None, **kwargs):
 
         if not HAS_CONSUL:
-            raise AnsibleError('python-consul is required for consul_kv lookup. see http://python-consul.readthedocs.org/en/latest/#installation')
+            raise AnsibleError('python-consul is required for consul_kv lookup. see https://python-consul.readthedocs.io/en/latest/#installation')
 
         values = []
         try: