Refresh specs for Dir.exists? and File.exists?

This follows upstream change ruby/spec#1065

spec/core/dir/exist_spec.rb

@@ -13,3 +13,11 @@
 
   it_behaves_like :dir_exist, :exist?
 end
+
+ruby_version_is "3.2" do
+  describe "Dir.exists?" do
+    it "has been removed" do
+      Dir.should_not.respond_to?(:exists?)
+    end
+  end
+end

spec/core/file/exist_spec.rb

@@ -4,3 +4,11 @@
 describe "File.exist?" do
   it_behaves_like :file_exist, :exist?, File
 end
+
+ruby_version_is "3.2" do
+  describe "File.exists?" do
+    it "has been removed" do
+      File.should_not.respond_to?(:exists?)
+    end
+  end
+end

spec/shared/file/exist.rb

@@ -4,11 +4,6 @@
     @object.send(@method, 'a_fake_file').should == false
   end
 
-  it "returns true if the file exist using the alias exists?" do
-    @object.send(@method, __FILE__).should == true
-    @object.send(@method, 'a_fake_file').should == false
-  end
-
   it "raises an ArgumentError if not passed one argument" do
     -> { @object.send(@method) }.should raise_error(ArgumentError)
     -> { @object.send(@method, __FILE__, __FILE__) }.should raise_error(ArgumentError)