[DOC] Fix output examples containing old Hash#inspect format

The inspect format was intentionally changed as an outcome of
[Bug #20433] [ruby-core:118668], but some documentation update
was missing, as [Bug #20962] pointed out. Update some output
examples that clearly use Hash#inspect.

array.c

@@ -5084,7 +5084,7 @@ rb_ary_concat(VALUE x, VALUE y)
  *  When string argument +string_separator+ is given,
  *  equivalent to <tt>self.join(string_separator)</tt>:
  *
- *    [0, [0, 1], {foo: 0}] * ', ' # => "0, 0, 1, {:foo=>0}"
+ *    [0, [0, 1], {foo: 0}] * ', ' # => "0, 0, 1, {foo: 0}"
  *
  */
 

doc/syntax/pattern_matching.rdoc

@@ -247,7 +247,7 @@ The "rest" part of a pattern also can be bound to a variable:
   else
     "not matched"
   end
-  #=> "matched: 1, {:b=>2, :c=>3}"
+  #=> "matched: 1, {b: 2, c: 3}"
 
 Binding to variables currently does NOT work for alternative patterns joined with <code>|</code>:
 

hash.c

@@ -3490,7 +3490,7 @@ inspect_hash(VALUE hash, VALUE dummy, int recur)
  *  Returns a new String containing the hash entries:
 
  *    h = {foo: 0, bar: 1, baz: 2}
- *    h.inspect # => "{:foo=>0, :bar=>1, :baz=>2}"
+ *    h.inspect # => "{foo: 0, bar: 1, baz: 2}"
  *
  */
 

object.c

@@ -3827,7 +3827,7 @@ rb_String(VALUE val)
  *
  *    String([0, 1, 2])        # => "[0, 1, 2]"
  *    String(0..5)             # => "0..5"
- *    String({foo: 0, bar: 1}) # => "{:foo=>0, :bar=>1}"
+ *    String({foo: 0, bar: 1}) # => "{foo: 0, bar: 1}"
  *
  *  Raises +TypeError+ if +object+ cannot be converted to a string.
  */