Add type specifier for Drupal\Component\Assertion\Inspector (#834)

* Add type specifier for Drupal\Component\Assertion\Inspector (#826)

* WIP

* WIP

* WIP

* WIP

* Fix CI errors

* Try TypeCombinator instead of UnionType

---------

Co-authored-by: Matt Glaman <nmd.matt@gmail.com>
(cherry picked from commit f7bc280)

* fix compatibility with 1.x

* adjust tests for 1.x

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Co-authored-by: Nikita Malyshev <niklanrus@gmail.com>

Author: mglaman

extension.neon

@@ -335,3 +335,7 @@ services:
 		class: mglaman\PHPStanDrupal\DeprecatedScope\DeprecationHelperScope
 		tags:
 			- phpstan.deprecations.deprecatedScopeResolver
+	-
+		class: mglaman\PHPStanDrupal\Type\InspectorTypeExtension
+		tags:
+			- phpstan.typeSpecifier.staticMethodTypeSpecifyingExtension