docs(json-path): add testing part doc for the component

Updates the documentation to document `JsonPathAssertionsTrait` and related constraints (closes #20977). Complete the previous work done in #21078.

# Conflicts:
#	components/json_path.rst

# Conflicts:
#	components/json_path.rst

Author: vinceAmstoutz

components/json_path.rst

@@ -216,7 +216,7 @@ appropriate (e.g., inside a ``filter()`` expression).
 Testing with JSON Assertions
 ----------------------------
 
-The component provides a set of PHPUnit assertions to make testing JSON data more convenient. To use them, include the
+The component provides a set of PHPUnit assertions to make testing JSON data more convenient. Use the
 :class:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait` in your test class::
 
     use PHPUnit\Framework\TestCase;
@@ -237,52 +237,52 @@ The component provides a set of PHPUnit assertions to make testing JSON data mor
 The trait provides the following assertion methods:
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathCount`
-    Asserts that the number of elements found by the JSONPath expression matches an expected count::
+  Asserts that the number of elements found by the JSONPath expression matches an expected count::
 
-        $json = '{"a": [1, 2, 3]}';
-        self::assertJsonPathCount(3, '$.a[*]', $json);
+      $json = '{"a": [1, 2, 3]}';
+      self::assertJsonPathCount(3, '$.a[*]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathEquals`
-    Asserts that the result of a JSONPath expression is equal (``==``) to an expected value. This assertion uses type coercion::
+  Asserts that the result of a JSONPath expression is equal to an expected value.The comparison uses ``==`` (type coercion) instead of ``===``::
 
-        $json = '{"a": [1, 2, 3]}';
+      $json = '{"a": [1, 2, 3]}';
 
-        // passes because "1" == 1
-        self::assertJsonPathEquals(['1'], '$.a[0]', $json);
+      // passes because "1" == 1
+      self::assertJsonPathEquals(['1'], '$.a[0]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathNotEquals`
-    Asserts that the result of a JSONPath expression is not equal (``!=``) to an expected value::
+  Asserts that the result of a JSONPath expression is not equal to an expected value.The comparison uses ``!=`` (type coercion) instead of ``!==``::
 
-        $json = '{"a": [1, 2, 3]}';
-        self::assertJsonPathNotEquals([42], '$.a[0]', $json);
+      $json = '{"a": [1, 2, 3]}';
+      self::assertJsonPathNotEquals([42], '$.a[0]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathSame`
-    Asserts that the result of a JSONPath expression is identical (``===``) to an expected value. This is a strict comparison and does not perform type coercion::
+  Asserts that the result of a JSONPath expression is identical (``===``) to an expected value. This is a strict comparison and does not perform type coercion::
 
-        $json = '{"a": [1, 2, 3]}';
+      $json = '{"a": [1, 2, 3]}';
 
-        // fails because "1" !== 1
-        // self::assertJsonPathSame(['1'], '$.a[0]', $json);
+      // fails because "1" !== 1
+      // self::assertJsonPathSame(['1'], '$.a[0]', $json);
 
-        self::assertJsonPathSame([1], '$.a[0]', $json);
+      self::assertJsonPathSame([1], '$.a[0]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathNotSame`
-    Asserts that the result of a JSONPath expression is not identical (``!==``) to an expected value::
+  Asserts that the result of a JSONPath expression is not identical (``!==``) to an expected value::
 
-        $json = '{"a": [1, 2, 3]}';
-        self::assertJsonPathNotSame(['1'], '$.a[0]', $json);
+      $json = '{"a": [1, 2, 3]}';
+      self::assertJsonPathNotSame(['1'], '$.a[0]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathContains`
-    Asserts that a given value is found within the array of results from the JSONPath expression::
+  Asserts that a given value is found within the array of results from the JSONPath expression::
 
-        $json = '{"tags": ["php", "symfony", "json"]}';
-        self::assertJsonPathContains('symfony', '$.tags[*]', $json);
+      $json = '{"tags": ["php", "symfony", "json"]}';
+      self::assertJsonPathContains('symfony', '$.tags[*]', $json);
 
 * :method:`Symfony\\Component\\JsonPath\\Test\\JsonPathAssertionsTrait::assertJsonPathNotContains`
-    Asserts that a given value is NOT found within the array of results from the JSONPath expression::
+  Asserts that a given value is NOT found within the array of results from the JSONPath expression::
 
-        $json = '{"tags": ["php", "symfony", "json"]}';
-        self::assertJsonPathNotContains('java', '$.tags[*]', $json);
+      $json = '{"tags": ["php", "symfony", "json"]}';
+      self::assertJsonPathNotContains('java', '$.tags[*]', $json);
 
 Error Handling
 --------------