GH-38940: [Ruby] Fix spelling (#38941)

### Rationale for this change

### What changes are included in this PR?

Spelling fixes to ruby/

### Are these changes tested?

### Are there any user-facing changes?

* Closes: #38940

Authored-by: Josh Soref <2119212+jsoref@users.noreply.github.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>

ruby/red-arrow/lib/arrow/array.rb

@@ -250,7 +250,7 @@ def resolve(other_array)
             "[array][resolve] need to implement " +
             "a feature that building #{value_data_type} array " +
             "from raw Ruby Array"
-          raise NotImpelemented, message
+          raise NotImplemented, message
         end
         other_array
       elsif other_array.respond_to?(:value_data_type)

ruby/red-arrow/lib/arrow/sort-key.rb

@@ -79,9 +79,9 @@ def try_convert(value)
     #     target and corresponding order is used. `"+"` uses ascending
     #     order and `"-"` uses ascending order.
     #
-    #     If `target` is not a String nor `target` doesn't start with the
-    #     leading order mark, sort column target is `target` as-is and
-    #     ascending order is used.
+    #     If `target` is either not a String or `target` doesn't start
+    #     with the leading order mark, sort column is `target` as-is
+    #     and ascending order is used.
     #
     #   @example String without the leading order mark
     #     key = Arrow::SortKey.new("count")