chore(deps): bump gettext from 0.17.0 to 0.18.0

Bumps [gettext](https://github.com/elixir-lang/gettext) from 0.17.0 to 0.18.0.
- [Release notes](https://github.com/elixir-lang/gettext/releases)
- [Changelog](https://github.com/elixir-gettext/gettext/blob/master/CHANGELOG.md)
- [Commits](elixir-gettext/gettext@v0.17.0...v0.18.0)

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

Author: dependabot-preview[bot]

mix.exs

@@ -57,7 +57,7 @@ defmodule GroupherServer.Mixfile do
       {:ecto_sql, "~> 3.2.0"},
       {:phoenix_ecto, "~> 4.0"},
       {:postgrex, ">= 0.14.1"},
-      {:gettext, "~> 0.17.0"},
+      {:gettext, "~> 0.18.0"},
       {:plug_cowboy, "~> 2.0"},
       {:plug, "~> 1.8.0"},
       # GraphQl tool

mix.lock

@@ -34,7 +34,7 @@
   "fs": {:hex, :fs, "0.9.2", "ed17036c26c3f70ac49781ed9220a50c36775c6ca2cf8182d123b6566e49ec59", [:rebar], [], "hexpm"},
   "gen_stage": {:hex, :gen_stage, "0.14.2", "6a2a578a510c5bfca8a45e6b27552f613b41cf584b58210f017088d3d17d0b14", [:mix], [], "hexpm", "1f201083ca2ee1ea2b8e1eb6e98d9842ef93f2e5efa2d602740ab0c56c2bc90b"},
   "gen_state_machine": {:hex, :gen_state_machine, "2.0.5", "9ac15ec6e66acac994cc442dcc2c6f9796cf380ec4b08267223014be1c728a95", [:mix], [], "hexpm", "5cacd405e72b2609a7e1f891bddb80c53d0b3b7b0036d1648e7382ca108c41c8"},
-  "gettext": {:hex, :gettext, "0.17.0", "abe21542c831887a2b16f4c94556db9c421ab301aee417b7c4fbde7fbdbe01ec", [:mix], [], "hexpm", "e0b8598e802676c81e66b061a2148c37c03886b24a3ca86a1f98ed40693b94b3"},
+  "gettext": {:hex, :gettext, "0.18.0", "406d6b9e0e3278162c2ae1de0a60270452c553536772167e2d701f028116f870", [:mix], [], "hexpm", "c3f850be6367ebe1a08616c2158affe4a23231c70391050bf359d5f92f66a571"},
   "guardian": {:hex, :guardian, "2.0.0", "5d3e537832b7cf35c8674da92457b7be671666a2eff4bf0f2ccfcfb3a8c67a0b", [:mix], [{:jose, "~> 1.8", [hex: :jose, repo: "hexpm", optional: false]}, {:plug, "~> 1.3.3 or ~> 1.4", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "6804b9eea4a30cab82bf51f1ae7ae333980b3bdcc6535b018242c4737e41e042"},
   "hackney": {:hex, :hackney, "1.15.1", "9f8f471c844b8ce395f7b6d8398139e26ddca9ebc171a8b91342ee15a19963f4", [:rebar3], [{:certifi, "2.5.1", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "6.0.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "1.0.1", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "~>1.1", [hex: :mimerl, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "1.1.4", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}], "hexpm", "c2790c9f0f7205f4a362512192dee8179097394400e745e4d20bab7226a8eaad"},
   "idna": {:hex, :idna, "6.0.0", "689c46cbcdf3524c44d5f3dde8001f364cd7608a99556d8fbd8239a5798d4c10", [:rebar3], [{:unicode_util_compat, "0.4.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "4bdd305eb64e18b0273864920695cb18d7a2021f31a11b9c5fbcd9a253f936e2"},