[ci skip] Fix return values of Hash Extensions examples

The hashes returned in some examples of the following sections had items in a different order than their receivers. That may mislead readers into believing those methods will not preserve element order.

Extensions to Hash/Working with Keys/transform_keys and transform_keys!
Extensions to Hash/Working with Keys/stringify_keys and stringify_keys!
Extensions to Hash/Working with Keys/symbolize_keys and symbolize_keys!
Extensions to Hash/Slicing

guides/source/active_support_core_extensions.md

@@ -2661,7 +2661,7 @@ The method `transform_keys` accepts a block and returns a hash that has applied
 
 ```ruby
 {nil => nil, 1 => 1, a: :a}.transform_keys { |key| key.to_s.upcase }
-# => {"" => nil, "A" => :a, "1" => 1}
+# => {"" => nil, "1" => 1, "A" => :a}
 ```
 
 In case of key collision, one of the values will be chosen. The chosen value may not always be the same given the same hash:
@@ -2703,7 +2703,7 @@ The method `stringify_keys` returns a hash that has a stringified version of the
 
 ```ruby
 {nil => nil, 1 => 1, a: :a}.stringify_keys
-# => {"" => nil, "a" => :a, "1" => 1}
+# => {"" => nil, "1" => 1, "a" => :a}
 ```
 
 In case of key collision, one of the values will be chosen. The chosen value may not always be the same given the same hash:
@@ -2745,7 +2745,7 @@ The method `symbolize_keys` returns a hash that has a symbolized version of the
 
 ```ruby
 {nil => nil, 1 => 1, "a" => "a"}.symbolize_keys
-# => {1=>1, nil=>nil, :a=>"a"}
+# => {nil=>nil, 1=>1, :a=>"a"}
 ```
 
 WARNING. Note in the previous example only one key was symbolized.
@@ -2822,7 +2822,7 @@ Ruby has built-in support for taking slices out of strings and arrays. Active Su
 
 ```ruby
 {a: 1, b: 2, c: 3}.slice(:a, :c)
-# => {:c=>3, :a=>1}
+# => {:a=>1, :c=>3}
 
 {a: 1, b: 2, c: 3}.slice(:b, :X)
 # => {:b=>2} # non-existing keys are ignored