Trial to use certifi 2.13.0

.github/workflows/tests.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        otp: ['23']
+        otp: ['21', '23']
         elixir: ['1.10', '1.11']
         global-mock: [true, false]
         include:

mix.exs

@@ -33,6 +33,7 @@ defmodule ExVCR.Mixfile do
       {:httpoison, "~> 1.0 or ~> 2.0", optional: true},
       {:finch, "~> 0.16", optional: true},
       {:excoveralls, "~> 0.18", only: :test},
+      {:certifi, "~> 2.13.0", only: :test, override: true},
       {:http_server, github: "parroty/http_server", only: [:dev, :test]},
       {:ex_doc, ">= 0.0.0", only: :dev}
     ]

mix.lock

@@ -1,6 +1,6 @@
 %{
   "castore": {:hex, :castore, "1.0.1", "240b9edb4e9e94f8f56ab39d8d2d0a57f49e46c56aced8f873892df8ff64ff5a", [:mix], [], "hexpm", "b4951de93c224d44fac71614beabd88b71932d0b1dea80d2f80fb9044e01bbb3"},
-  "certifi": {:hex, :certifi, "2.12.0", "2d1cca2ec95f59643862af91f001478c9863c2ac9cb6e2f89780bfd8de987329", [:rebar3], [], "hexpm", "ee68d85df22e554040cdb4be100f33873ac6051387baf6a8f6ce82272340ff1c"},
+  "certifi": {:hex, :certifi, "2.13.0", "e52be248590050b2dd33b0bb274b56678f9068e67805dca8aa8b1ccdb016bbf6", [:rebar3], [], "hexpm", "8f3d9533a0f06070afdfd5d596b32e21c6580667a492891851b0e2737bc507a1"},
   "cowboy": {:hex, :cowboy, "1.1.2", "61ac29ea970389a88eca5a65601460162d370a70018afe6f949a29dca91f3bb0", [:rebar3], [{:cowlib, "~> 1.0.2", [hex: :cowlib, repo: "hexpm", optional: false]}, {:ranch, "~> 1.3.2", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "f4763bbe08233eceed6f24bc4fcc8d71c17cfeafa6439157c57349aa1bb4f17c"},
   "cowlib": {:hex, :cowlib, "1.0.2", "9d769a1d062c9c3ac753096f868ca121e2730b9a377de23dec0f7e08b1df84ee", [:make], [], "hexpm", "db622da03aa039e6366ab953e31186cc8190d32905e33788a1acb22744e6abd2"},
   "earmark": {:hex, :earmark, "1.4.3", "364ca2e9710f6bff494117dbbd53880d84bebb692dafc3a78eb50aa3183f2bfd", [:mix], [], "hexpm", "8cf8a291ebf1c7b9539e3cddb19e9cef066c2441b1640f13c34c1d3cfc825fec"},