Bump credo from 1.0.2 to 1.0.3 (#49)

Bumps [credo](https://github.com/rrrene/credo) from 1.0.2 to 1.0.3.
- [Release notes](https://github.com/rrrene/credo/releases)
- [Changelog](https://github.com/rrrene/credo/blob/master/CHANGELOG.md)
- [Commits](rrrene/credo@v1.0.2...v1.0.3)

Signed-off-by: dependabot[bot] <support@dependabot.com>

mix.lock

@@ -1,7 +1,7 @@
 %{
   "bunt": {:hex, :bunt, "0.2.0", "951c6e801e8b1d2cbe58ebbd3e616a869061ddadcc4863d0a2182541acae9a38", [:mix], []},
   "certifi": {:hex, :certifi, "2.5.1", "867ce347f7c7d78563450a18a6a28a8090331e77fa02380b4a21962a65d36ee5", [:rebar3], [{:parse_trans, "~>3.3", [hex: :parse_trans, repo: "hexpm", optional: false]}], "hexpm"},
-  "credo": {:hex, :credo, "1.0.2", "88bc918f215168bf6ce7070610a6173c45c82f32baa08bdfc80bf58df2d103b6", [:mix], [{:bunt, "~> 0.2.0", [hex: :bunt, optional: false]}, {:jason, "~> 1.0", [hex: :jason, optional: false]}]},
+  "credo": {:hex, :credo, "1.0.3", "5278e8953f379b41ebe27c75c96d2e154ebc3f75dfe057c8b68c39133c25bb9f", [:mix], [{:bunt, "~> 0.2.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm"},
   "dialyxir": {:hex, :dialyxir, "0.5.1", "b331b091720fd93e878137add264bac4f644e1ddae07a70bf7062c7862c4b952", [:mix], []},
   "earmark": {:hex, :earmark, "1.3.1", "73812f447f7a42358d3ba79283cfa3075a7580a3a2ed457616d6517ac3738cb9", [:mix], []},
   "ex_doc": {:hex, :ex_doc, "0.19.3", "3c7b0f02851f5fc13b040e8e925051452e41248f685e40250d7e40b07b9f8c10", [:mix], [{:earmark, "~> 1.2", [hex: :earmark, optional: false]}, {:makeup_elixir, "~> 0.10", [hex: :makeup_elixir, optional: false]}]},