Minor documentation correction on 'context' & 'defaults'

To ensure the YAML structure correctly assigns 'context' & 'defaults' as
dicts the elements under context & defaults need an extra set of
indents.

Example:

- example:
  test: 1

Compiles to: [{'example': None, 'test': 1}]

While:

- example:
    test: 1

Correctly compiles to: [{'example': {'test': 1}}]

doc/man/salt.7

@@ -6800,10 +6800,10 @@ makes use of the jinja templating system would look like this:
     \- mode: 644
     \- template: jinja
     \- context:
-      custom_var: "override"
+        custom_var: "override"
     \- defaults:
-      custom_var: "default value"
-      other_var: 123
+        custom_var: "default value"
+        other_var: 123
 .ft P
 .fi
 .sp

salt/states/file.py

@@ -22,10 +22,10 @@ makes use of the jinja templating system would look like this:
         - mode: 644
         - template: jinja
         - context:
-          custom_var: "override"
+            custom_var: "override"
         - defaults:
-          custom_var: "default value"
-          other_var: 123
+            custom_var: "default value"
+            other_var: 123
 
 Directories can be managed via the ``directory`` function. This function can
 create and enforce the permissions on a directory. A directory statement will