Normalize more booleans. (#5247) (#5250)

(cherry picked from commit 015566fb06)

Co-authored-by: Felix Fontein <felix@fontein.de>

plugins/cache/pickle.py

@@ -16,7 +16,7 @@ DOCUMENTATION = '''
     author: Brian Coca (@bcoca)
     options:
       _uri:
-        required: True
+        required: true
         description:
           - Path in which the cache plugin will save the files
         env:

plugins/cache/redis.py

@@ -21,7 +21,7 @@ DOCUMENTATION = '''
           - The format is C(host:port:db:password), for example C(localhost:6379:0:changeme).
           - To use encryption in transit, prefix the connection with C(tls://), as in C(tls://localhost:6379:0:changeme).
           - To use redis sentinel, use separator C(;), for example C(localhost:26379;localhost:26379;0:changeme). Requires redis>=2.9.0.
-        required: True
+        required: true
         env:
           - name: ANSIBLE_CACHE_PLUGIN_CONNECTION
         ini:

plugins/cache/yaml.py

@@ -16,7 +16,7 @@ DOCUMENTATION = '''
     author: Brian Coca (@bcoca)
     options:
       _uri:
-        required: True
+        required: true
         description:
           - Path in which the cache plugin will save the files
         env: