Adjust JSON Pointer examples (#3622)

* 📝 adjust JSON Pointer examples

* 👷 add test for documentation

* 📝 note platform-dependent output on some examples

docs/mkdocs/docs/api/basic_json/basic_json.md

@@ -317,6 +317,8 @@ basic_json(basic_json&& other) noexcept;
     --8<-- "examples/basic_json__CompatibleType.output"
     ```
 
+    Note the output is platform-dependent.
+
 ??? example "Example: (5) create a container (array or object) from an initializer list"
 
     The example below shows how JSON values are created from initializer lists.

docs/mkdocs/docs/api/basic_json/max_size.md

@@ -40,7 +40,7 @@ string elements the JSON value can store which is `1`.
 
 ??? example
 
-    The following code calls `max_size()` on the different value types. Note the output is implementation specific.
+    The following code calls `max_size()` on the different value types.
         
     ```cpp
     --8<-- "examples/max_size.cpp"
@@ -52,6 +52,8 @@ string elements the JSON value can store which is `1`.
     --8<-- "examples/max_size.output"
     ```
 
+    Note the output is platform-dependent.
+
 ## Version history
 
 - Added in version 1.0.0.

docs/mkdocs/docs/api/basic_json/meta.md

@@ -32,8 +32,7 @@ Constant.
 
 ??? example
 
-    The following code shows an example output of the `meta()`
-    function.
+    The following code shows an example output of the `meta()` function.
     
     ```cpp
     --8<-- "examples/meta.cpp"
@@ -45,6 +44,8 @@ Constant.
     --8<-- "examples/meta.output"
     ```
 
+    Note the output is platform-dependent.
+
 ## See also
 
 - [**NLOHMANN_JSON_VERSION_MAJOR**/**NLOHMANN_JSON_VERSION_MINOR**/**NLOHMANN_JSON_VERSION_PATCH**](../macros/nlohmann_json_version_major.md) - library version information

docs/mkdocs/docs/api/basic_json/std_hash.md

@@ -26,6 +26,8 @@ type of the JSON value is taken into account to have different hash values for `
     --8<-- "examples/std_hash.output"
     ```
 
+    Note the output is platform-dependent.
+
 ## Version history
 
 - Added in version 1.0.0.