Update {Method,UnboundMethod,Proc}#source_location signatures to match Ruby 4.1

* Needed for ruby/ruby#15580

Author: eregon

core/method.rbs

@@ -400,7 +400,7 @@ class Method
   # This method will return `nil` if the method was not defined in Ruby (i.e.
   # native).
   #
-  def source_location: () -> [String, Integer]?
+  def source_location: () -> ([String, Integer]? | [String, Integer, Integer, Integer, Integer]?)
 
   # <!--
   #   rdoc-file=proc.c

core/proc.rbs

@@ -845,7 +845,7 @@ class Proc
   # This method will return `nil` if the Proc was not defined in Ruby (i.e.
   # native).
   #
-  def source_location: () -> [String, Integer]?
+  def source_location: () -> ([String, Integer]? | [String, Integer, Integer, Integer, Integer]?)
 
   # <!--
   #   rdoc-file=proc.c

core/unbound_method.rbs

@@ -300,7 +300,7 @@ class UnboundMethod
   # This method will return `nil` if the method was not defined in Ruby (i.e.
   # native).
   #
-  def source_location: () -> [String, Integer]?
+  def source_location: () -> ([String, Integer]? | [String, Integer, Integer, Integer, Integer]?)
 
   # <!--
   #   rdoc-file=proc.c

test/stdlib/Method_test.rb

@@ -154,8 +154,14 @@ def test_receiver
   end
 
   def test_source_location
-    assert_send_type  '() -> [String, Integer]',
-                      METHOD, :source_location
+    if_ruby(..."4.1") do
+      assert_send_type  '() -> [String, Integer]',
+                        METHOD, :source_location
+    end
+    if_ruby("4.1"...) do
+      assert_send_type  '() -> [String, Integer, Integer, Integer, Integer]',
+                        METHOD, :source_location
+    end
     assert_send_type  '() -> nil',
                       method(:__id__), :source_location
   end

test/stdlib/Proc_test.rb

@@ -139,8 +139,14 @@ def test_parameters
   end
 
   def test_source_location
-    assert_send_type  '() -> [String, Integer]',
-                      proc{}, :source_location
+    if_ruby(..."4.1") do
+      assert_send_type  '() -> [String, Integer]',
+                        proc{}, :source_location
+    end
+    if_ruby("4.1"...) do
+      assert_send_type  '() -> [String, Integer, Integer, Integer, Integer]',
+                        proc{}, :source_location
+    end
     assert_send_type  '() -> nil',
                       Proc.new(&Kernel.method(:print)), :source_location
   end

test/stdlib/UnboundMethod_test.rb

@@ -89,10 +89,18 @@ def test_parameters
   end
 
   def test_source_location
-    assert_send_type  '() -> [String, Integer]?',
-                      UMETH, :source_location
-    assert_send_type  '() -> [String, Integer]?',
-                      ParamMeths.instance_method(:leading_optional), :source_location
+    if_ruby(..."4.1") do
+      assert_send_type  '() -> [String, Integer]?',
+                        UMETH, :source_location
+      assert_send_type  '() -> [String, Integer]',
+                        ParamMeths.instance_method(:leading_optional), :source_location
+    end
+    if_ruby("4.1"...) do
+      assert_send_type  '() -> [String, Integer, Integer, Integer, Integer]?',
+                        UMETH, :source_location
+      assert_send_type  '() -> [String, Integer, Integer, Integer, Integer]',
+                        ParamMeths.instance_method(:leading_optional), :source_location
+    end
   end
 
   def test_super_method